U.S Defence Secretary Robert Gates has said that there would have to be a pretty significant deterioration in the security situation in Iraq before he would consider delaying the planned withdrawal of nearly half the remaining U.S. troops in the country by September 1. Mr. Gates was responding to a statement by the U.S. commander in Iraq, Army General Ray Odierno, who has said he presented plans to Gates and other senior officials for a possible slowdown in the withdrawal if next month's elections in Iraq lead to instability. Odierno said he does not expect to seek a delay and that he has accelerated the early part of the withdrawal. He said he will ask for a slowdown if he feels it is necessary. Mr. Gates indicated that only a serious change in the much-improved security situation in Iraq would justify such a move.