BAGHDAD — The U.S. is abandoning plans to keep U.S. troops in Iraq past a year-end withdrawal deadline, The Associated Press has learned. The decision to pull out fully by January will effectively end more than eight years of U.S. involvement in the Iraq war, despite ongoing concerns about its security forces and the potential for instability.

The decision ends months of hand-wringing by U.S. officials over whether to stick to a Dec. 31 withdrawal deadline that was set in 2008 or negotiate a new security agreement to ensure that gains made and more than 4,400 American military lives lost since March 2003 do not go to waste.

In recent months, Washington has been discussing with Iraqi leaders the possibility of several thousand American troops remaining to continue training Iraqi security forces. A Pentagon spokesman said Saturday that no final decision has been reached about the U.S. training relationship with the Iraqi government.

But a senior Obama administration official in Washington confirmed Saturday that all American troops will leave Iraq except for about 160 active-duty soldiers attached to the U.S. Embassy.

A senior U.S. military official confirmed the departure and said the withdrawal could allow future but limited U.S. military training missions in Iraq if requested.

Both officials spoke on condition of anonymity because of the sensitivity of the issue.