Taleban leader Mullah Omar and al-Qaeda commanders, including Osama Bin Laden, are living in Pakistan, a senior US official has told reporters.
Mullah Omar (C) and Taleban leaders are still at large
He said senior Taleban leaders were in hiding with Mullah Omar in Quetta, from where they co-ordinated the insurgency in Afghanistan.
He also reiterated Washington's belief that Bin Laden was taking refuge in Pakistan's western tribal areas.
Islamabad repeatedly denies that Mullah Omar or Bin Laden are in Pakistan.
The US official, speaking on condition of anonymity in Washington, told reporters:
"There is no question that the iconic leaders of al-Qaeda - (Ayman al-)Zawahiri, Bin Laden... are in the tribal areas of Pakistan.
"We believe that the Taleban's shura (consultation) council leaders led by Mullah Omar reside in Quetta in Pakistan," he said.
The official, who did not give a source for his information, said al-Qaeda was doing its planning in the tribal areas "just as Mullah Omar is giving strategic direction for the Taleban from Quetta".
Quetta is the capital of rugged Balochistan province which borders Afghanistan.
Last month, captured Taleban spokesman Muhammad Hanif made similar claims about Mullah Omar's whereabouts, which were rejected by Pakistan.
Mr Hanif said Mullah Omar was protected by Pakistan's Inter-Services Intelligence agency.
Afghan President Hamid Karzai made similar allegations last year. The ISI was instrumental in backing the Taleban after civil war swept Afghanistan following the withdrawal of Soviet troops in 1989.