President George W. Bush and Prime Minister Gordon Brown said at a news conference after talks at No. 10 Downing Street they remain committed to success in Iraq and Afghanistan and agree that tougher sanctions are needed on Iran if it ignores demands to suspend uranium enrichment. On troop withdrawals in Iraq, Bush said, 'the plan is bring them home based on success. That's what we expect the British prime minister to do. That's what I'm doing.'