U.S. President Barack Obama has called his Pakistani counterpart to offer condolences over 24 Pakistani soldiers killed in a NATO airstrike.
The White House said Obama told Asif Ali Zardari that the deaths were "regrettable" but that they were not the result of a deliberate attack.
He reiterated his call for a "full investigation" of the November 26 incident and said the relationship with Pakistan was critical to the security interests of both nations.
Earlier, U.S. Secretary of State Hillary Clinton spoke with Pakistani Prime Minister Yousaf Raza Gilani about the incident.
The State Department said Clinton again offered U.S. condolences over the deaths.
The two calls came just ahead of an international conference in Germany
on the future of Afghanistan, a conference Pakistan says it is boycotting because of the incident.
Pakistan also said NATO would not be able to use supply lines to Afghanistan and was demanding the United States abandon a base used to launch drone strikes.
Plus, the Pakistani military has decided its soldiers deployed along the border with Afghanistan can return fire if attacked.
compiled from agency reports