US President George W Bush on Thursday endorsed his top commander in Iraq's recommendation to halt US troop withdrawals once the surge ends in July, leaving open the possibility that 140,000 soldiers will still be in Iraq when he leaves office, according to dpa. Bush offered his strong support to General David Petraeus, who called for A 45-day pause in troop reductions after the buildup ends to assess the effect of the increased US presence ordered last year by the president to quell violence and sectarian killings. "I have told him he'll have all the time he needs" to determine whether additional cuts can take place, Bush said. Bush, acknowledging the strain on the US military, said he was ordering a 12-month limit to deployments in Iraq, reducing the length of troop rotations from 15 months. Bush's speech came after Petraeus, along with ambassador Ryan Crocker, on Wednesday completed two days of testimony before Congress to outline the progress that has been made in Iraq since the troop surge came into full effect last summer. Bush said that under the troop buildup the US and Iraqi governments have regained the initiative, sectarian violence has dropped and that al-Qaeda was on the defensive and "we're now working to deliver a crippling blow." "With the surge, a major strategic shift has occurred," Bush said.