WASHINGTON (CNN) -- U.S. Defense Secretary Robert Gates said the United States would be prepared to reconcile with the Taliban if the Afghan government pursued talks to end the seven-year conflict in that country.

Gates made the comments to reporters Thursday while at a meeting of NATO defense ministers in Budapest, Hungary. The United States and NATO are looking for ways to reduce the rising violence in Afghanistan.

The Taliban has been battling a U.S.-led coalition since it was toppled from power in 2001 for harboring Osama bin Laden's al Qaeda terrorist network.

U.S. commanders in Afghanistan have asked for an additional 15,000 troops but the call has gone unanswered, with the United States short on troops and NATO countries not interested in contributing more personnel.

Alternatively, a plan is being developed under the direction of the chairman of the Joint Chiefs of Staff, Adm. Mike Mullen, focused on the idea that Afghanistan and Pakistan are linked by a common insurgency that stretches along their border, according to a Pentagon official with knowledge of the issue.

The official would not go on the record because he did not want to speak about the plan before Mullen introduces it.

Mullen said empowering tribal militias that have influence in both Pakistan -- where U.S. forces have limited access -- and Afghanistan -- where the United States is training more Afghan security forces to bolster troop levels -- could reduce violence.

By giving legitimate power to some militias, the plan addresses U.S. commanders' frustration with Afghan President Hamid Karzai's government, which is viewed as not very effective outside the capital, Kabul.

The official said that no decisions have been made and no drafts have been shown to Mullen, but the plan is expected to be completed later this year. There is no political timeline attached to the report, according to the official.

Gates, referring to talks with the Taliban, said a similar rapprochement strategy worked in Iraq.

"We promoted a reconciliation that involved people we were pretty confident had been shooting at us and killing our soldiers," he said.

"At the end of the day, that's how most wars end," Gates said, referencing the Sunni Awakening Movement in Iraq.

"There has to be ultimately -- and I'll underscore ultimately -- reconciliation as part of a political outcome to this," he said

Those talks would not include al Qaeda, Gates said.

The reconciliation would have to be on the Afghan government's terms, and the Taliban would have to subject itself to the sovereignty of the government, he added.

"That's ultimately the exit strategy for all of us," Gates said.

All About Afghanistan • The Taliban • NATO • Robert Gates