A U.S. military exercise believed to be a rehearsal for a war with Iraq ended Tuesday in the Gulf nation of Qatar, a senior official said.

The computer-assisted war game began Dec. 9 and involved thousands of senior officers and their staff around the world. It was designed to test the ability of the U.S. Central Command, normally based in Tampa, Fla., to control a regional war from a new, portable headquarters that was deployed to Qatar last month.

Led by Gen. Tommy Franks, Central Command would control U.S. military operations in any potential conflict with Iraq. The new $58 million portable headquarters allows Franks to move his staff anywhere in the command's 25-nation area of responsibility.

Such exercises are relatively common in the military, and normally don't attract much attention. But the timing and the proximity of Internal Look to Iraq has sparked speculation about the exact scenario the game was testing.

Central Command officials refused to discuss the details of the exercise, saying it was classified.

There had been speculation that Franks may have his senior officers remain in Qatar after the exercise ends, but spokesman Lt. Col. John Robinson had earlier said the headquarters staff would return home in mid-December. There was no definite word Tuesday on the command's next move.

Senior Central Command officials have said the command post will remain at Camp As Sayliyah, 10 miles outside of Doha, after the exercise ends. The dozens of tents and modular buildings are currently set up inside air-conditioned warehouses normally used to store heavy military equipment. Most of that equipment has been moved to Kuwait, on the border with Iraq.

How many troops, and at what ranks, will remain after the exercise is not clear.

President Bush has threatened military action against Iraq if it does not give up all weapons of mass destruction. U.N. weapons inspectors are currently checking Iraqi claims that it has no such weapons.

The war game gave Central Command's officers a chance to try out the deployable headquarters' cutting-edge technology, some of which is less than six months old, a senior officer said, on condition of anonymity. The exercise was successful in that some hitches were met and dealt with, the officer said.

The players for exercise Internal Look were limited to senior commanders — the key decision makers in any war — and did not include combat units, though commanders at the division and corps level observed the exercise via computer links.

Internal Look has been held periodically since 1990, but this is the first time Central Command has set up the new portable headquarters for the exercise. It is also the first time Internal Look has been held outside the United States.