BAGHDAD - The US military is not in Iraq "to seize anybody's oil," Defense Secretary Jim Mattis said, distancing himself from remarks by President Donald Trump at the start of a visit to Iraq on Monday.Mattis, on his first trip to Iraq as Pentagon chief, is hoping to assess the war effort as US-backed Iraqi forces launch a new push to evict Islamic State militants from their remaining stronghold in the city of Mosul.But he is likely to face questions about Trump's remarks and actions, including a temporary ban on travel to the United States and for saying America should have seized Iraq's oil after toppling Saddam Hussein in 2003.Trump told CIA staff in January: "We should have kept the oil. But okay. Maybe you'll have another chance."Mattis, however, flatly ruled out any such intent. "We're not in Iraq to seize anybody's oil," he told reporters traveling with him.His remarks are the latest example of his policy differences with Trump. Trump has acknowledged that Mattis did not agree with him about the usefulness of torture as an interrogation tactic but, in a sign of Mattis' influence, said he would defer the matter to his defense secretary.