WASHINGTON, Feb 20 (Reuters) - Taliban insurgents will increasingly threaten Afghan stability after international forces withdraw in December, and Kabul will need more troops than currently envisioned to provide basic security, according to a new independent strategy review.
The assessment, conducted by the Center for Naval Analyses and obtained by Reuters on Thursday, warned that plans to shrink the size of the Afghan National Security Force to 228,500 from the current 382,000 would put the U.S. policy of preventing the country from becoming a safe haven for extremists "at risk."
"We recommend that the international community establish a new plan to fund and sustain the ANSF at an end strength of about 373,400, with a proportionally sized assistance mission (including advisers), through at least 2018," said the report by the center, part of a nonprofit research and analysis group.
The 378-page CNA report, requested in a law passed by Congress, will pressure the legislature to consider additional support for Afghan forces for several more years, even as the Pentagon is facing huge cuts to its own budget.
The Center for Naval Analyses is part of nonprofit research and analysis organization CNA.
The United States and NATO are currently trying to finalize the shape of any international military mission that would stay in Afghanistan after December to support to Afghan troops.
A final decision has been thrown into doubt by President Hamid Karzai's refusal to sign a bilateral security agreement with the United States ahead of presidential elections in April.
Washington has said it would have to withdraw all American forces if no deal is signed. Officials hope Afghan elections beginning April 5 produce a victor willing to sign the accord.
Rear Admiral John Kirby, the top Pentagon spokesman, told a news conference the department had received the CNA report but was not yet prepared to discuss its findings.
He acknowledged that Taliban rebels remained a threat.
"We never take our eye off the Taliban insurgency or the threat they pose, not just to us and to our allies, but to the Afghan people," Kirby said.
Still, he said Defense Secretary Chuck Hagel "is committed" to the finding of the NATO summit in Chicago that calls for reducing the overall size of the ANSF, which is funded with support from the international community.
The CNA report also found that Afghan security forces will continue to have gaps in critical military capabilities in 2015 and beyond, including air support, logistics and intelligence gathering and analysis.
"We therefore conclude that international enabler support - to include advisers - will be essential to ANSF through at least 2018," it said.
The report also said a small group of al Qaeda members would continue to be active in Afghanistan, having intermarried with local clans and forged ties with Afghan and Pakistani militants.
Kirby acknowledged Afghan forces still need outside help, saying that is one reason the international alliance there has been pursuing a post-2014 mission to continue building the ANSF's military capabilities.
"It's a commitment we made long ago," he said. "It's a commitment we're trying to make now on the ground in Afghanistan to improve their capacity and capability." (Reporting by David Alexander and Phil Stewart)