The situation in Holland has deteriorated rapidly. The Dutch army, having already been severely tested, withdraws into their 'central bastion' which covers their three main cities: The Hague, Amsterdam and Rotterdam. With their backs against the sea, the Dutch army is cut off from the Franco-Belgian forces and notably from Giraud's Army which is moving to their aid.

As a result of the German move toward Moerdyck, the French 7th Army is exposed on its right flank. Gen Giraud decides that his vanguard has ventured too far northward and should be pulled back to the line Berg-op-Zoom-Lierre in order to regroup west of the Escaut River. With this move he is abandoning his mission which was the recapture of Rotterdam and the support of the Dutch forces. The 9th Panzer

Corap's 9th Army is defending the west bank of the Meuse from Namur upstream to Mézières, Huntziger's 2nd Army from a point just east of Mézières to the western end of the Maginot line. Corap's army is one of the weakest. He has 7 infantry divisions, only 2 of which are regular, the 5th Motorized and the 4th North African. 2 reserve divisions, the 61st and the 53rd, are series B divisions, badly armed, overaged and undertrained. 1 division, the 102nd, is a fortress division and has no transport. Corap hopes to get his army into place by May 14, but his cavarly is quickly ejected from the Ardennes the previous day. He orders his infantry to speed up their advance. By the evening of the 12th only half of the 18th Division's infantry battalions are in place and only 5 battalions of the 22nd Div are in their designated positions. Upon arriving in their designated positions they find no fortifications which the Belgian high command led them to believe were there. Corap learns during the evening that German troops are approaching the Meuse, and all his units are not yet in place.

Rommel's 7th Panzer Div approaches the Meuse opposite Corap's army. A motorcycle reconnaissance patrol discovers an ancient weir near Houx that has not been destroyed for fear the water level would drop making a crossing easier. Several companies scramble across during the night.

German infantry is now crossing the Albert Canal at Vroenhoven in great numbers. The Liège hinge is forced. The Belgian front is also broken in the area of Tongres. The Belgians begin to fall back on to the line Anvers-Louvain with the intention of basing their defense on Namur.

6 British Fairey bombers attempt to knock out the bridges over the Maas River, one at Vroenhoven and one at Veldwezelt. German fighters and anti-aircraft betteries are already set up to defend. One bridge sustains some damage, but the Germans quickly repair it. All the bombers are shot down except 1 which returns due to engine trouble. French bombers try at midday, but they are also unable to knock them out.

The German attack on Prioux's position in the Gembloux Gap opens with intense bombing by Stukas, followed by a heavy barrage from the tanks of the 3rd and 4th Panzer Divs. They hit the center of Prioux's line at Hannut, but are stopped by the end of the day. The battlefield is littered with an equal number of knocked out tanks from both sides. The Germans outnumber Prioux here, 824 to 520 in armored vehicles.

By 6am Guderian's tanks are across the Semois and threatening to collapse Huntziger's left flank. At Bouillon Lt-Col Herman Balck's 1st Rifle Regt finds a ford in the Semois River and soon the lead tanks from the 1st Panzer Div cross the same ford. German engineers quickly build a bridge on which the rest of the tanks cross. By midmorning tanks from the 1st Panzer are racing down the road to Sedan only 10 miles away.

At 4pm Gen Guderian drives up to the fighting-line and urges his units on. 'Keep going! Keep going!' he shouts. 'Don't stop!' The French cavalry, which can bring in only a dozen tanks in this sector, is swept off the roads. It takes refuge in the woods and can do little to slow down the enemy's advance. It has inflicted as much damage as it can beyond the Meuse, but this damage does not have much effect. The German engineers are very skilled at re-riveting.

In the evening, from Dinant to Sedan, the Germans are either level with the Meuse or within easy reach of it and are fighting with the French infantry all along the line. Throughout the night German motorized columns roar toward the battle with all their lights showing.

During the night the French 71st Div arrives at the Meuse near Sedan. It is to be placed between the 55th Infantry Div and the 3rd North African, all part of the French X Corps under the command of Gen Claude Grandsard. He assures Gen Baudet, Commander of the 71st, that he will have plenty of time to get his men in place. During the afternoon, however, Grandsard had watched the approach of 2 different panzer divisions, 1 in the St. Menges area 2 miles north of Sedan, and the other in the outskirts of Sedan. French artillery or bombers could have wreaked havoc on either of these formations since they were packed tightly emerging from the Ardennes. Artillery is being saved for a French counterattack and the air force had been informed that they were not needed as there was more than enough artillery to handle the job.

Guderian flies to Ebly to meet with Kleist. Kleist order him to attack the next day at 3pm. Guderian protests that his 2nd Panzer Div will not be up yet nor the corps artillery. Kleist refuses to delay for those reasons and says a coordinated aerial bombardment on the French postions will take place before the attack. Guderian's three-pronged attack plan starts with the 1st Panzer Div in the center to cross the Meuse at Glair, half-mile downstream from Sedan. After scaling Marfée Woods, they are to push southward to a line running from the villages of Chéhéry to Chaumont, about 2 miles soutn of Sedan. If the 2nd Panzer arrives in time, it will be on the right flank and cross at Donchéry, 2 miles west of Sedan. Next it will occupy the heights of the Croix-Piot just south of the river. The 10th Panzer on the left flank is to cross just to the southeast of Sedan near Bazeilles, across from the village of Wadelincourt. They then will occupy the heights to the south of the river. The brunt of the attack will be made by the 3 battalions of Lt-Col Hermann Balck's 1st Rifle Regt, and 4 battalions of Col Graf von Schwerin's Grossdeutschland Regt along with a number of assault engineer companies. Their job will be to cross the river, establish a bridgehead on far bank and hold until the engineers can build a bridge over which the panzers can cross. Once across Guderian plans to pivot to the west and plunge into the French rear. To protect his southern flank, the Grossdeutschland Regt or the 10th Panzer Div or both will occupy the heights of the Mont Dieu Woods and the nearby town of Stonne, 10 miles south of Sedan.