Obama Announces Thousands of Troops Will Remain In Afghanistan Beyond 2016

— -- President Obama announced today his decision to extend the U.S. military mission in Afghanistan, leaving thousands of troops in the country beyond 2016.

"As commander in chief, I will not allow Afghanistan to be used as a safe haven for terrorists to attack our nation again," Obama said. "Afghan forces are still not as strong as they need to be."

The president made the announcement in the White House alongside Vice President Joe Biden, Defense Secretary Ash Carter and Chairman of the Joint Chiefs of Staff Joseph Dunford.

Obama announced the United States will keep 9,800 troops in Afghanistan through most of 2016 before drawing down to about 5,500 by the end of the year.

It’s a significant reversal for the president, who sees “ending two wars” as one of his greatest achievements. The president had planned to withdraw virtually all U.S. troops from the country by the end of 2016 except those needed to protect the U.S. embassy in Kabul.

In response to a shouted question from reporters in the room at the end of his remarks, Obama said his decision was “not disappointing.”

“My goal has been to ensure that we give every opportunity for Afghanistan to succeed,” Obama said. “This isn’t the first time those adjustments have been made and this probably won’t be the last.”

In 2014, the president announced the U.S. mission in Afghanistan would decrease from 9,800 troops to 1,000 by the end of 2016.

The troops will be stationed in Jalalabad, Kandahar, Kabul and Bagram, Obama said, but he did not give a timeframe for when the force level will decrease from 9,800 to 5,500, saying it is a decision that will be made in consultation with commanders on the ground and allies.

The troops will be tasked with conducting two non-combat missions – a counter-terrorism mission to go after Al Qaeda and threats to the homeland and to train, advise and assist Afghan security forces.

The decision comes after a months-long comprehensive review that begin this past spring and included conversations among Obama, Afghan President Ghani, and Afghan Chief Executive Officer Abdullah.

While the announcement coincides with the Taliban’s capture of Kunduz last month, the plan to keep thousands of troops in Afghanistan was being considered and reviewed for months, senior administration officials told ABC News.

During congressional testimony last week, Gen. John Campbell, the top U.S. commander in Afghanistan, recommended leaving more than the 1,000 troops after 2016 in order to adequately train Afghan security forces and focus on counter-terrorism efforts.

This new plan is estimated to cost $14.6 billion in 2017, compared to the $10 billion projected for the president’s previous proposal.

While Republicans welcomed the announcement today, they also said the plan to maintain troop levels would not be sufficient to advance U.S. interests in Afghanistan.

“The House of Representatives will closely review this announcement, but let’s be clear: maintaining the status quo in Afghanistan is not a plan for success,” House Speaker John Boehner, R-Ohio, wrote in a statement. “The president’s half-measures and failed leadership have emboldened our enemies and allowed for ISIL’s rise,” using the government’s preferred acronym for ISIS.

ABC's Ben Siegel contributed to this report.