Nov. 10 (Bloomberg) -- President Barack Obama will discuss four options for a buildup of U.S. forces in Afghanistan when he meets tomorrow with his national security team, White House spokesman Robert Gibbs said.

Gibbs, speaking to reporters traveling with the president to Fort Hood, Texas, declined to give details on those options.

Obama is under pressure to make a decision on whether to grant a request by his top commander in the field, General Stanley McChrystal, to send 40,000 more troops. That would expand the 68,000-strong U.S. force that will be in Afghanistanby the end of the year, including 21,000 that Obama authorized earlier this year.

To contact the reporter on this story: Roger Runningen in Washington at rrunningen@bloomberg.net

Last Updated: November 10, 2009 12:01 EST