The November 26, 2011 attack on Salala checkpost further deteriorated already tense relations between Pakistan and the United States. -File Photo

ISLAMABAD: American attempts to rebuild its relationship with Pakistan appear to be deadlocked on the issue of a US apology for killing 24 Pakistani border troops last November.

US officials visited Pakistan on Friday for talks on rebooting the relationship, but left without agreement.

A statement from the Pakistani president's office said Asif Ali Zardari told the US officials that Washington needed to help Pakistan reach ''closure'' over the killings of the soldiers on the Afghan border by following recommendations by the Pakistani parliament.

The parliament has asked for Washington to apologize for the incident. The United States has expressed regret, but has declined to say it is sorry.