The most senior military officer in the US has accused Pakistan's intelligence agency of aiding Afghan militants in an attack on the US embassy in Kabul last week.
Admiral Mike Mullen, told the US Senate that the insurgent Haqqani network, which has claimed responsibility for the attack that killed 25 people last Tuesday, acted as a "veritable arm of Pakistan's Inter-Services Intelligence Agency (ISI)".
"With ISI support, Haqqani operatives planned and conducted a truck bomb attack, as well as the assault on our embassy," he said.
The Haqqani network is named after its founder Jalaluddin Haqqani, and is based in the North Waziristan area of Pakistan.
Mullen is not the first senior US official to openly question Islamabad's suspected links to the Haqqani network.
On Saturday the U.S. Ambassador to Pakistan, Cameron Munter, issued a similar warning on Pakistani radio.
"There is evidence linking the Haqqani network to the Pakistan government. This is something that must stop," he said.
The claims come as a senate committee threatened to make financial aid to Islamabad conditional on the Pakistani government cracking down on Afghan insurgence operating out of its territory.