WASHINGTON, Sept 11 (Reuters) - U.S. President George W. Bush plans to give a speech on his Iraq strategy at 9 p.m. EDT on Thursday (0100 GMT on Friday), the White House said. Bush will discuss his strategy in Iraq after the U.S. commander, Gen. David Petraeus told Congress in two days of testimony that he believed U.S. forces there could be drawn down by about 30,000 by next summer. That would bring the troop levels back to where they were before the "surge" Bush ordered at the start of this year. The White House said Bush would request live coverage of the speech by major U.S. television networks but aides declined to discuss the substance of Bush's speech.