Italian Prime Minister Silvio Berlusconi has informed US President George Bush about his decision to start withdrawing his country's troops from Iraq starting in September. Meanwhile, White House Press Secretary Scott McClellan said Italian troop withdrawal would not affect military operations in Iraq, pointing out that it "will be based on the ability and capability of Iraqi forces and the Iraqi government to be able to assume more responsibility." Earlier on Wednesday US President Bush's staunchest ally in the Iraq war, British Prime Minister Tony Blair issued a statement trying to play down the significance of Berlusconi's announcement. He insisted that the timing of coalition troops' withdrawal would depend on the ability of the Iraqi government to provide adequate security structures.