Washington's delegation left Islamabad Friday night with no breakthroughs on healing the rift, which has been aggravated by last November's U.S. friendly fire airstrike on Pakistani troops and the more-recent terrorist raids in Afghanistan.
"This is the beginning of the re-engagement conversation," State Department spokeswoman Victoria Nuland said in Washington. "We're going to have to work through these issues, and it's going to take some time."
The New York Times said a major sticking point has been Pakistan's demand for an apology over the air strike that killed two dozen of its soldiers along the Afghan border. Sources told the newspaper the Obama administration was considering the gesture until earlier this month when terrorists believed to be operating out of Pakistan struck downtown Kabul, raising questions about the role Pakistani intelligence may have played in the incident. "What changed was the 15th of April," a senior administration official said.
Sources said despite the sticking points, the two sides were at least satisfied that a dialogue between the two wary allies was taking place and new ideas for constructive change were being proposed.
'SNL': 'Anchorman 2' cast, One Direction sing 'Afternoon Delight' [VIDEO]
Ukrainian protestors topple Lenin statue [VIDEO]