Top U.S. military commanders most likely to direct an attack on Iraq will gather in snowy southern Germany this month for exercises to strengthen ties between U.S.-based troops and the U.S. Army's Heidelberg-based V Corps.

The commanders and more than 1,000 headquarters staff will coordinate simulated artillery, air and helicopter attacks deep into an enemy's rear area from a mobile headquarters in the Army's sprawling Grafenwoehr training grounds.

The exercise -- dubbed Victory Scrimmage -- is classified, but a U.S. military official, speaking on condition of anonymity, said troops from the 101st Airborne Division and the 1st Cavalry Division will be sent from the United States to practice Iraq invasion scenarios for seven to 10 days in late January and early February.

Together with V Corps' 1st Armored Division and the 1st Infantry Division, the four divisions are among the Army's best-equipped and combat ready.

"This is a grouping that is actually going to fight the war if necessary in Iraq, and they have to do these exercises to get their procedures right and for the officers to get to know each other," said retired British Army Maj. Charles Heyman, editor of Jane's World Armies.

"These are the formations we've kept our eyes on for quite a long time, so the pieces of the jigsaw are falling into place."

Lt. Col. Joseph Richard, a V Corps spokesman, said it will be the first time the units from the United States will travel to Europe for an exercise with V Corps -- the Army's only corps overseas with more than 40,000 personnel.

"It's an opportunity to work out any particular challenges we may experience," Richard said. "We're talking about significant numbers of organizations and soldiers, and it's important to be able to flesh out these operations prior to any other operation we may have to undertake."

A corps is the largest tactical unit in the U.S. Army, and can control up to five divisions, while synchronizing actions by the Navy, Air Force and Marines. It was 7th Corps, based in Germany until disbanded in the early 1990s, that took the lead during the Gulf War.

Victory Scrimmage will be run by V Corps commander Lt. Gen. William Wallace, who spent much of December in Qatar with about 500 of his headquarters staff staging Internal Look, another classified exercise widely thought to have been a rehearsal for war with Iraq.

About one-fifth of his staff stayed behind, and several other V Corps units, including the 130th Engineer Brigade and the 205th Military Intelligence Brigade, were ordered to the region by mid-February.

During the exercise, the headquarters staff will set up a corps command post -- the kind that can be airlifted in entirety to a combat area -- and then run computer simulated command and control exercises, Richard said. Like Internal Look, it will not involve combat units on the ground.

"It's all part of normal military preparedness," Heyman said. "They'd be hostages to fortune if they didn't do it ... and they will probably have to do it again with troops on the ground as a field training exercise once they get on the ground in the Gulf."

Gathering the four divisions for war games close to when the first major report by U.N. weapons inspectors is due, Jan. 27, is also a way to show Baghdad that Washington is serious.

"There is a psychological operation going on both at the diplomatic and military level, and it's there to convince Saddam Hussein and the Iraqi army that resistance is futile," Heyman said.