A joint session of Parliament recently adopted a resolution that demanded an unconditional apology from the US for the attack.
Islamabad's insistence on an apology has held up efforts to put Pakistan-US ties back on an even keel after a year of crises, including the NATO attack and the unilateral American raid that killed Osama bin Laden.
Pakistan's participation in a crucial NATO Summit to be held in Chicago from May 20 too has been linked to the resetting of ties with the US.
Speaking at the end of Gilani's five-day visit to Britain, Khar, however, said Pakistan's decision to close the supply routes was the correct one.
In this regard, she recalled the NATO air strike and the American "incursion" to kill bin Laden.
Khar described the operation against the Al Qaeda chief as an effort by the US to take sole credit for finding bin Laden.
Regarding Pakistan's supposed obligation to keep the supply routes open, given that the presence of foreign troops in Afghanistan is an United Nations-mandated mission, Khar said Islamabad was not "bound" as the UN resolution only called for "facilitation." She rubbished reports of sanctions being slapped on Pakistan because of the closure of the supply routes.
However, Khar was not forthcoming on when exactly the supply routes would be reopened and was hesitant to even give a timeframe.
When questioned on what the stumbling block was, she said that negotiations are underway and that "goodwill" is needed. She negated reports that the US had declined to apologise for the NATO attack.