New US Defense Secretary Robert Gates, in an unannounced trip to the battlefront, said on Wednesday he discussed with American commanders the possibility of boosting US troop strength in Iraq but has made no decisions about what to do. On just his third day in his post, Gates journeyed to Iraq armed with a mandate from US President George W. Bush to help forge a new Iraq war strategy. His goal is to get advice from his top military commanders on a new strategy for the increasingly unpopular, costly and chaotic war - a conflict that Bush conceded Tuesday the US is not winning. "We discussed the obvious things," Gates told reporters after meeting with top US generals. "We discussed the possibility of a surge and the potential for what it might accomplish." Gates said he was only beginning the process of determining how to reshape US policy in the war. He said before making final decisions, he would also confer with top Iraqi officials about what the future American role in the country should be. Gates spoke to reporters after meeting with commanders including Army Gen. John Abizaid, commander of US forces in the Middle East, and Gen. George Casey, the top American commander in Iraq. Abizaid and Casey have both raised questions in the past about the value of sending thousands of extra troops into Iraq, where violence has been rising in recent months. Several top US commanders have been wary of even a short-term troop increase, saying it might only bring a temporary respite to the violence while confronting the US with shortages of fresh troops in the future. Asked about a possible surge of US troops, Casey repeated his concern that "additional troops have to be for a purpose." Gates and the generals did not cite any figures or timetables for a possible troop increase. Among the proposals Bush is considering is buttressing the 140,000 US troops currently in Iraq to try to control surging violence in Baghdad and the unabated Sunni insurgency in Anbar province. Extra forces would also make it easier for the US to increase the number of American advisers for Iraqi security forces. Meanwhile, at a year-end news conference, Bush said the United States will "ask more of our Iraqi partners" in 2007, and he pledged to work with the new Democratic Congress, as well. Bush sidestepped a question on whether he would order a so-called surge of troops in Iraq as a first step toward gaining control of the violent and chaotic sitation there. "Nice try," he told a reporter who asked about his plans. The bipartisan Iraq Study Group recommended a quick buildup of troops as part of an overall plan to arrest what it called a "grave and deteriorating" situation in Iraq. Bush also said the United States supports the creation of a unity government in Iraq. The president opened the question and answer session by conceding the obvious - things have not gone well in Iraq, where the United States has lost more than 2,900 troops in more than four years of war, without quelling the insurgency. "The enemies of liberty ... carried out a deliberate strategy to foment sectarian violence between Sunnis and Shia. And over the course of the year they had success," he said. "Their success hurt our efforts to help the Iraqis rebuild their country. They set back reconciliation and kept Iraq's unity government and our coalition from establishing security and stability throughout the country."