Members of the pro-Taliban Jamiat ulema-i-Islam party protest in Quetta on Thursday, May 28, 2009, against the military offensive against Taliban in Swat. AP Photo.

According to the Telegraph, the US has threatened to expand the airstrike campaign to include the Quetta Shura, the Afghan Taliban's governing council led by Mullah Omar:

State department and intelligence officials delivered the ultimatum to Asif Ali Zardari, Pakistan's president, last week as he visited the US for the United Nations' security council sessions and the G20 economic summit.

Pakistan's government has argued the Quetta Shura, led by Mullah Mohammad Omar, does not harm Pakistan. It has said that dealing with other militants such as those in the Swat valley was a higher priority.

But last week Anne Patterson, America's ambassador to Islamabad, told the Daily Telegraph that the offensive in Swat was not targeting the insurgents posing the greatest danger to Nato forces in Afghanistan.

An official at the Pakistani interior ministry told the Daily Telegraph: "The Americans said we have been raising this issue with you time and again. These elements are attacking Nato forces in southern Afghanistan, especially in Helmand. The Americans said 'If you don't take action, we will.'"

Rehman Malik, Pakistan's interior minister, said the US had so far been unable to provide detailed intelligence to target the Quetta Shura. He said: "We need real-time intelligence. The Americans have never told us any location."

Malik makes a similar argument when discussing the government's failure to move against Lashkar-e-Taiba leader Hafiz Saeed.

According to this report at the Times Online, Pakistan's Inter-Service Intelligence agency is moving senior Taliban leaders to the port city of Karachi, effectively putting them out of reach.

Taking the air war to the Taliban in Pakistan's major cities is a different ballgame than striking at compounds and camps in the villages in Pakistan's tribal areas. The US would have to strike in populated centers, and the risk of civilian casualties would be far greater. And putting boots on the ground, an option listed in the Telegraph article, in a city like Quetta, would be impossible without direct Pakistani support, which will not be forthcoming.