Washington ? The Pentagon announced Monday that more than 92,000 troops will be in the next rotation of U.S. forces in Iraq, and Defense Secretary Donald H. Rumsfeld said its exact size will not be decided until after the Dec. 15 election of a new Iraqi government.

The Pentagon said it has identified some of the major combat units that will deploy, starting in mid-2006 as part of a rotation that will run through mid-2008, including a unit from Fort Riley, Kan.

It said the identified units will total about 92,000 troops, but Rumsfeld said that should not be taken as the final figure.

The number of troops in future rotations will depend on conditions, as well as the recommendations of U.S. commanders, Rumsfeld said.

The Pentagon hopes to be able to reduce U.S. troop levels as Iraqi security forces become more capable of defending their own country, but it is unclear when that point will be reached.

Officials also disclosed that U.S. commanders in Iraq decided they would not need one brigade until early next year. It had been scheduled to deploy to Iraq before the Dec. 15 election. That unit, the 1st Brigade, 1st Infantry Division, based at Fort Riley, Kan., will deploy after the election instead.