The Wehrmacht's official communiqué announces the previous day's successes in clarion tones: 'In the west, after a series of partial successes, the greatest offensive of all time has had its first strategic result: our forces have reached the sea.'

At Lord Gort's headquarters, preparations are made for the action decided on in Lens the day before. At 12:30pm the commander of the BEF receives a message from Gen Blanchard informing him that French forces will not be able to move until May 22nd or the night after mainly because the roads are so heavily blocked. Gort, who has prepared his action for May 21st and is fully aware of the importance of the time factor, decides to ignore the message and launches his attack towards Arras at 2pm. This action, commanded by Gen Franklyn, is carried out by the British 5th and 50th Divisions and 100 heavy and light tanks with protection on their western flank provided by the 3rd Light Mechanized Division.

Martel had planned to begin his attack at 2pm. Since only one infantry brigade is available then, he decides to delay half an hour. When no others showe he launched his attack anyway. Without infantry or aerial assistance, he expected his tank brigade to reach Cambrai less than 20 miles from the Somme River in two days. Martel is surprised when fighting breaks out almost immediately. His right column, led by 4th Tank Regiment, meets an enemy force at Duisans. After a brief fight, the village is cleared. Prisoners are taken, but the bulk of column continues on toward Warlus, which is captured after overcoming more German resistance. The column then moves on to Berneville and throws an advance guard across Doullens-Arras road, but is pinned down by machine-gun and mortar fire as well as a 20-minute Luftwaffe bombardment. Martel's tanks continue their sweep around the left flank of the German position and push on to Wailly. Near Wailly, Martel's tanks run into truckloads of German infantry of the SS Totenkopf Division moving to catch up to Rommel's tanks a few miles ahead. Shocked to discover their anti-tank shells bounce off the British armor, the German troops break and run. A large number of prisoners is taken by the Durham Light Infantry Regiment. The unofficial estimate puts the number at 400 prisoners. There is no record of what happened to them. The Germans believe that as many as 400 SS soldiers were murdered by members of Durham Light Infamtru. They will soon retaliate in kind.

While Martel's right column is stopped near Wailly, his left column led by the 7th Tank Regiment, manages to penetrate German flank more deeply capturing 4 villages along the way. About 3pm a German transport column is annihilated in Dainville. Advancing another two miles they overrun a German anti-tank battery whose 37-mm armor-piercing shells bounce off the Matildas. The main force continues south to Mercatel which it reaches about 4:20pm. A smaller British force advances as far as Wancourt on the Cojeul River where it is stopped by some German 88mm anti-aircraft guns which prove highly effective at penetrating Allied armor.

Having stopped British counterattack, Rommel launches one of his own at 6pm. He orders the 25th Panzer Regiment to retrace its steps and attack southeastward to take the British tanks in the flank and rear. They strike at Warlus and Duisans which is also heavily bombed by Luftwaffe. Gen Franklyn tries to get RAF help but his request has to pass thru too many hands and the request is never received at the airfield in Kent. Martel decides to pull his forces back under cover of approaching darkness, since he does not have enough infantry to hold the ground that the tanks had won. He returns to his starting positions north of Arras about 2am on May 22. They had penetrated the German panzer corridor to a depth of 10 miles, knocked out about 20 tanks and captured over 400 prisoners. In the 9-hour battle the British had lost 46 tanks (62% of their total) and did not reach day's objective, the Cojeul River. Had the British had infantry support, Rommel would have been hard pressed to defend against simultaneous attacks on two of his flanks. Because of this attack, which the Germans believed was made by about 5 divisions, the 10th Panzer Division is withdrawn from Guderian's command so it can be used to check any additional British counterattacks in the Arras area. In so doing, this weakened Guderian's drive on the Channel ports ultimately making it possible for the Allied evacuation from Dunkirk.

Rommel provides his account of the battle of Arras:

While violent scraps were going on in the Tilloy-Beaurains-Agny sector, powerful armored forces had swarmed out of Arras, subjecting us to heavy losses in men and equipment. The anti-tank guns that we speedily brought into action proved too light to be effective against the heavily armored British tanks. Most of them were put out of action by the enemy artillery - likewise their crews. A large number of vehicles were set on fire. SS units in the vicinity (including the Death's-head Div) had to fall back under the weight of the attack. Finally the divisional artillery and some 88-mm anti-aircraft guns managed to halt the enemy armor south of a line from Beaurains to Agny...

'The losses suffered by the 7th Panzer Div in the course of the day,' states the Division's official history, 'were 89 killed, 116 wounded and 173 missing, or 4 times the losses suffered during the initial breakthrough and the early days of the invasion of France.' The fighting ends at nightfall.

By 8pm the armor of the 3rd Light Mechanized Division, which has captured Warlus and Gimencourt in the course of the afternoon, has been spent. It has covered so many miles since May 10th that the worn caterpillars are beginning to break. In any case, this is the end of the line for them. Bardies comments: 'Gen Franklyn's attack could have maintained its impetus only had it been strengthened and supported by the French on the left.' This operation ends up being the only serious counterattack launched by the encircled armies. It has extensive psychological consequences:

1. On the British side: It convinces Lord Gort once and for all that the only way out for the BEF is to withdraw to Dunkirk, turning its back on any attempt to cut through to the south.

2. On the German side: It jolts the morale of the High Command to an extent quite out of proportion with the material results.

'Gens Kluge and Kleist were particularly disturbed,' writes Rommel. 'Kluge was in favor of delaying any resumption of the westward advance till the situation in the Arras sector had righted itself.'

Guderian's panzer divisions spent day waiting for orders. The German high command did not know what to do with the panzers once they reached the coast. Late in the day orders arrive. He is to swing northward and seize the Channel ports to trap the BEF before it can reach the sea. Each division is assigned one port: Calais to the 1st Panzer; Boulogne to the 2nd; and Dunkirk to the 10th. Guderian soon receives word from von Kleist that the 10th will be held in reserve in case of additional Allied counterattacks along the panzer corridor. Dunkirk will have to wait. The move on the other two ports will begin the next morning.

At 3pm, after an extremely eventful journey, Gen Weygand drives into Ypres, where an important inter-Allied conference is to be held. Neither Gen Ironside (who had returned to London 24 hours earlier), nor Lord Gort, nor any representative of the RAF is present. The representatives wait for Gort for some time, but, since time is pressing, they decide to start without him. Gen Weygand outlines his plan of operations. It consists of simultaneously striking southward from around Cambrai and northward from the Somme, so as to reknit the two branches of the battle-line somewhere near Bapaume. This is the first suggestion of mounting a united counterattack, in place of the small local counterattacks that have been attempted to this point. Bardies writes:

That this effort was no longer to be centered on Sedan, as had previously been proposed, was due to the fact that Gen Weygand had estimated that German covering forces were now reinforced and solid in this sector and that it was too late to attack there. Furthermore, the action of the 1st Group of Armies would by that time have been too far from this attacking front to link up effectively with the action of the forces in the south.

Weygand examines the possibilites with King Leopold and Gen Billotte. The Belgians are to abandon the Escaut, which has become impossible to defend, and withdraw to the Yser where they can face eastward as in 1914. While they are thus protecting the left of the line, along a 55-mile front bounded on the right by the Lys, the French and British will attack southward, with 8 divisions, along the Bapaume-Cambrai front. They will meet up with the French forces located wouth of the Somme, which will simultaneously attack northward. The conference ended at 7pm.

[Here the plan was compromised by the unwillingness of the Belgians to leave their position on the plea that their troops were exhausted. All Gen Weygand could obtain was King Leopold's promise of a decision within 24 hours. - Ed]

After Gen Weygand's departure, King Leopold, Gen Billotte and Gen Fagalde discuss the problems arising from the withdrawal of the Belgian army. At present it is fighting between the Escaut and the Lys, its left wing still holding out between Gand and the sea. Gen Billotte pleads in favor of the retirement to the Yser advocated by Weygand. The maneuver could be carried out by pivoting on Halluin. This withdrawal will have the additional advantage of reducing the 55-mile front currently held by the Belgian army to one of 30 miles. King Leopold finally agrees in principle, but the decision is not clear cut.

Lord Gort finally reaches Ypres about 9pm. He finds the King of the Belgians, Gen Billotte and Gen Fagalde in conference. He apologizes for not arriving earlier, blaming the congested roads. Gen Weygand wants to launch a heavy attack southward so as to break through the encirclement of the units fighting in Flanders and enable them to pull back south of the Somme. Lord Gort wants to withdraw in a northeasterly direction, toward the Channel ports, so as to ensure the BEF's evacuation to England. He refrainsd from saying so and his silence prompts this reproach from Gen Fagalde: 'You must do what has been agreed!' In short, nothing positive comes out of the Ypres conference.

Once again misfortune strikes the Allied High Command. While Gen Billotte is heading back to his headquarters, his car collides with a van in Locre. He is gravely injured and at once falls into a coma. He will die on May 23rd without regaining consciousness.

For a day and a half there is no overall command. On May 23rd Gen Blanchard is to replace Gen Billotte as head of the 1st Group of Armies, while Gen Prioux will succeed Blanchard as commander of the 1st Army. The Cavalry Corps, previously under Prioux, will be taken over by Gen Langlois. The wavering caused by this accident is made even worse by the fact that the co-ordinating powers previously conferred on Gen Billotte are not sought for Gen Blanchard. Finally Gen Blanchard, who had not attended the Ypres conference, has only a hazy notion of Gen Weygand's plans.

At the end of the Ypres conference, after Gen Weygand had gone, Lord Gort and Adm Keyes discuss the difficult situation in which Gen Overstraeten has been placed. Britain's envoy to King Leopold takes the view that the plan to evacuate the BEF via Dunkirk is tantamount to running out on the Belgian army, but he does not have the nerve to tell the King. He describes the bitter feelings among the troops and at Belgian GHQ. Whereupon Gort, with a gesture of despondency, asks him: 'Do the Belgians really regard us as awful dirty dogs?'

Very late in the evening Gen Weygand returns to Paris. 'He had wasted precious hours,' writes Fabre-Luce, 'tracking down an absentee (Gort) and giving instructions to a man under sentence of death (Billotte).'