Having crossed the Rhine, both Army groups fanned out into the German hinterland. In the south, while the Third Army headed east, the First Army headed northeast and formed the southern pincer of the Ruhr envelopment. In the north, the U.S. Ninth Army, which since the Battle of the Bulge had been assigned to the 21st Army Group, headed southeast, forming the northern pincer, while the rest of the 21st Army Group went east and northeast. Even before the encirclement was complete, Allied activity against the Ruhr had a critical impact on Germany's economy—on March 26 Joseph Goebbels noted in his diary that no more coal was coming from the Ruhr.