WASHINGTON — The former top U.S. commander in Afghanistan today called on the White House to announce how many troops it intends to leave in that country after 2014.

Retired Gen. John Allen said Afghans need certainty on how many U.S. troops will stay behind after the majority complete their withdrawal by Dec. 31, 2014, before they will choose to side with the Afghan government or the Taliban.

“In the absence of clarity about the future, you’ll do what you know,” he said. “If ... taking no position ... has kept you alive,” Afghans will continue to hedge their bets, he said.

Allen was speaking as the Center for a New American Security released a new report by him, former top U.S. defense official Michele Flournoy and Brookings Institute’s defense expert Michael O’Hanlon.

The report warns the United States and its allies could risk losing any achievements if the drawdown ahead of the December 2014 deadline is accelerated, or if the international community skimps on continuing aid to the country after 2014.

All three urged the Obama administration to announce troop numbers

“I’d like to see it soon,” Allen said. “What the president has said to the Afghans is we will not abandon you. What is missing right now ... are the specifics associated with that.”

Allen had recommended a post-2014 U.S. force of 13,600, he said, supported by additional NATO troops. Officials have said they are considering a range of between 8,000 and 12,000 troops.