"John Kerry's pessimism, shifting positions and lack of resolve will not win the fight against the terrorists. His campaign has demonstrated again that it has nothing to offer but attacks on the president's agenda for creating a safer world," Ken Mehlman said in a statement out Saturday.

"On the eve of (Iraqi) Prime Minister (Iyad) Allawi's visit to the United States, John Kerry's military adviser is preaching defeat and suggesting retreat in Iraq. Such a withdrawal would be a victory for the terrorists and a defeat for freedom everywhere," the statement added.

"John Kerry must explain if this is his new position on Iraq," Mehlman said.

Kerry, in turn, has accused Bush of hiding a plan aimed at calling up reservists to serve in Iraq until just after the November 2 presidential vote.

White House spokesman Scott McClellan said Friday that "it's just another baseless attack from Senator Kerry. He's struggling to explain his incoherent positions on Iraq, and just engaging in baseless attacks."