WASHINGTON: The United States and Pakistan are working on the language of a possible US apology to end their stalemate and reopen Nato’s supply routes to Afghanistan, diplomatic sources told Dawn.

Pakistan wants the United States to apologise over a Nov 26 air raid that killed 24 Pakistani soldiers at the Salala military post. The United States had initially agreed to apologise but changed its mind after aides warned President Barack Obama the move could harm his re-election campaign.

Pakistan closed Nato’s supply routes to Afghanistan after the raid and is refusing to reopen them unless the Americans apologise.

The sources who spoke to Dawn said they “now see a stronger desire on both sides” to resolve this dispute.

They said the two sides had already exchanged several drafts of the expected apology and might soon agree “on a draft that meets everybody’s requirements”.

The sources rejected recent reports in the US media that Pakistan was refusing to reopen the routes because it wanted higher tariffs from the United States for using its highways.

A team of US experts has been based in Islamabad for the past six weeks, trying to end the dispute and reopen the supply routes. On Friday, another senior US official, Assistant Secretary of Defence Peter Levoy, also joined the team.

Meanwhile, Pakistan’s ambassador in Washington, Sherry Rehman, urged US officials to avoid making remarks that could further deteriorate an already tense relationship between the two countries. Commenting on Secretary Panetta’s recent statement that the United States was losing patience with Pakistan, Ambassador Rehman said: “This kind of public messaging from a senior member of the US administration is taken very seriously in Pakistan, and reduces the space for narrowing our bilateral differences at a critical time in the negotiations.”

Such statements, she noted, “adds an unhelpful twist to the process and leaves little oxygen for those of us seeking to break a stalemate”.