U.S. officials say President George Bush's top defense aides are advising him to withdraw one combat brigade from Iraq, but not until next February.

The officials said Thursday the defense chiefs also proposed sending a combat brigade to Afghanistan early next year instead of to Iraq.

U.S. commanders have expressed hope that Iraq's sharp reduction in violence will free up more U.S. forces to fight an escalating insurgency in Afghanistan.

The United States now has 15 combat brigades in Iraq and more than 140,000 troops in total. A U.S. combat brigade has between 3,000 to 5,000 troops. The U.S. military contingent in Afghanistan numbers about 34,000.

US Defense Secretary Robert Gates (file photo)

The U.S. Defense Department says Defense Secretary Robert Gates and military chief Admiral Mike Mullen gave their recommendation to President Bush on Wednesday.

It did not disclose the content of their recommendation, which President Bush is now considering.

The Pentagon says the two officials also presented Mr. Bush with the views of the top U.S. commander in Iraq, General David Petraeus. It says the defense chiefs "fundamentally" agree about how to proceed with troop levels in Iraq.

General Petraeus said in an interview this week that American combat troops could be withdrawn from Baghdad by next July if security gains hold.

In other developments Thursday, the U.S. military says a bomb blast killed two American soldiers on patrol in eastern Baghdad.

The military also says coalition forces killed one terrorist and detained 15 suspects in operations against al-Qaida in Baghdad and the Tigris River Valley.

Elsewhere, the U.S. military says coalition troops captured a suspected terrorist leader involved in oil extortion at a refinery in the town of Beiji.

And U.S. troops arrested an Iraqi cameraman and three of his family members in Baghdad on suspicion of links to terrorism.

Some information for this report was provided by AP and Reuters.