The top American commander in Iraq said he was preparing recommendations on troop reductions before he returns to Washington next month for a report to Congress. He predicted the US footprint in Iraq would have to be "a good bit smaller" by next summer. But Gen. David Petraeus on Wednesday cautioned against a quick or significant US withdrawal that could surrender "the gains we have fought so hard to achieve." He declined to offer specifics on the upcoming recommendation. The report, expected next month, is seen as a potential roadmap for US military and diplomatic policies in Iraq. Petraeus also said the "horrific and indiscriminate attacks" that killed at least 250 Yazidis, an ancient religious sect, in northwestern Iraq on Tuesday were the work of al-Qaida in Iraq fighters.