ID=9589529WASHINGTON — President Obama will announce a plan to keep a contingency force of 9,800 U.S. troops in Afghanistan beyond 2014, according to senior administration and Pentagon officials.

Obama will make the announcement Tuesday afternoon, according to three senior administration officials. The officials, who were not authorized to speak publicly on the matter, asked not to be identified.

"He will make clear that we are open to continued efforts in Afghanistan on two narrow missions after 2014: training Afghan forces and supporting CT (counterterrorism) operations against the remnants of al-Qaeda," one official said. "We will only sustain a military presence after 2014 if the Afghan government signs the Bilateral Security Agreement."

A senior Pentagon official confirmed the two-pronged mission: training and counterterrorism.

According to Obama's plan, U.S. troop levels would would be reduced by about half, consolidating U.S. troops in Kabul and on Bagram Air Base, by 2015.

By the end of 2016, the U.S. "will draw down to a normal embassy presence with a security assistance office in Kabul, as we have done in Iraq," the official said.

The size of the post-2014 force makes sense, but the rationale for removing all of them is lacking, said Michael O'Hanlon, a military analyst at the Brookings Institution.

With 9,800 troops, the U.S. military can support about six bases along with their Afghan counterparts, O'Hanlon said. That force would could also maintain air bases, including drones, in key parts of the country.

Further reductions in 2015 could be justified as Afghan security forces improve. But a full withdrawal after 2016 would be a mistake, O'Hanlon said. He pointed to the experience in Germany, Britain, Korea and Japan, where U.S. forces remain long after wars have ended but the need to support strong allies remains.

"Where is the virtue in declaring now that the follow-on mission will only last two years?" O'Hanlon said. "It seems to me that keeping the American people safe should be the fundamental emphasis, not being able to say that we've totally departed."

Obama is scheduled to announce his plan in the White House Rose Garden at 2:45 p.m. ET.

The former commander of all forces in Afghanistan, Marine Gen. John Allen, had recommended more than 13,000 U.S. troops remain there after this year. And former Defense secretary Leon Panetta urged between 8,000 and 12,000.

Obama visited troops at Bagram on Sunday.