BAGHDAD — The U.S. military said today it understands a Turkish incursion into northern Iraq "is an operation of limited duration" specifically targeting Kurdish rebels.

The statement came after the Turkish military said on its Web site that it had sent ground forces across the border into Iraq in pursuit of Kurdish rebels after Turkish warplanes and artillery bombed suspected rebel targets.

Rear Adm. Gregory Smith, a U.S. spokesman in Iraq, said the military had received assurances from its NATO ally Turkey that it would do everything possible to avoid "collateral damage to innocent civilians or Kurdish infrastructure."

He said the Turkish operation was specifically targeting members of the Kurdistan Workers Party, or PKK.

"Multi-National Forces-Iraq is aware Turkish ground forces have entered into northern Iraq, for what we understand is an operation of limited duration to specifically target PKK terrorists in that region," Smith said in an e-mailed statement.

"The United States continues to support Turkey's right to defend itself from the terrorist activities of the PKK and has encouraged Turkey to use all available means, to include diplomacy and close coordination with the Government of Iraq to ultimately resolve this issue," he added.

TORONTO — Canada's prime minister unveiled a proposal on Thursday to withdraw his country's forces from volatile southern Afghanistan in 2011, a move that largely accedes to opposition demands amid threats of an early election.Stephen Harper's minority Conservative government is trying to extend past February 2009 the military operation in Kandahar province, a region that was once the Taliban's stronghold."It seems clear that we have moved significantly toward the kind of bipartisan consensus that can be presented to Parliament for ratification," Harper said.