WASHINGTON — A senior administration official today said President Barack Obama will tell the American people tonight U.S. troops will start leaving Afghanistan "well before" the end of his first term.

The rough outlines of a withdrawal plan will be part of the revamped Afghanistan strategy Obama will announce in a speech from West Point at 8 p.m.

He also will announce he is sending 30,000 more troops to Afghanistan over the next six months, an accelerated war escalation that would have the first Marines there as early as Christmas, one senior administration official said.

Another official said the exit strategy Obama outlines with the troop increase will have a starting point of sometime before the end of 2012.