The two top Republican Senators John McCain and Lindsey Graham have warned in a joint statement that "the US has been incredibly patient with Pakistan...despite certain undeniable and disturbing facts."
Citing "support of Pakistan army and intelligence to the Haqqani network and other terror groups blamed for attacks on US troops in Afghanistan," the senators said, "The time has come for the US to fully review its relations with Pakistan. We must assess the nature and levels of our support for Pakistan."
"In particular, all options regarding US security and economic assistance to Pakistan must be on the table, including substantial reductions and stricter standards for performance," they said.
They termed Islamabad's response to the North Atlantic Treaty Organisation's air strikes that reportedly killed 24 of its troops as "deeply troubling" and said this had added to continued deterioration in Pakistan-US ties.
McCain and Graham offered their deep condolences over those killed in the strike, which they described as "unfortunate and unintentional," and said that the military investigation would clarify the circumstances of the "terrible tragedy."
Lashing out at the Pakistan government's response to the events, the two senators said Islamabad was now preventing NATO supplies from reaching Afghanistan, ordering US intelligence officers to leave the country and boycotting the Bonn conference. They also referred to reports that Pakistan may have decided to suspend all bilateral counter-terrorism agreements and said, "Such steps by the Pakistan government would mark a new low for our relationship."
The two senators also called on the Obama administration to develop contingency plans for supplying troops in Afghanistan.
