ISLAMABAD, Nov 2: Richard G. Olson, the US Ambassador to Islamabad, was `called` to the Foreign Office on Saturday to formally protest the latest drone attacks carried out by Washington just nine days after a meeting between Prime Minister Nawaz Sharif and President Barack Obama.

The ambassador was called hours after media reports that the banned Tehreek-i-Taliban Pakistan`s chief Hakeemullah Mehsud had been killed in a drone strike in North Waziristan on Friday.

`In order to register our concerns, the US ambassador was called to the Foreign Office by the foreign secretary to register our protest over the recent drone attacks,` an official statement said.

`The latest drone strike will have a negative impact on the government`s initiative to undertake a dialogue with the TTP.

`The government, however, is determined to continue with these efforts to engage with the TTP to bring an end to the ongoing violence and make them a part of mainstream politics within the parameters of our constitution.

`In accordance with our publicly stated, consistent policy, Pakistan has con-demned drone strikes whenever they have taken place, including the two recent drone attacks that took place on Thursday and Friday.

The statement added that the latest strikes, which reportedly killed the TTP chief, would have a negative impact on the government`s initiative to hold dialogue with the Taliban.

It said the government had made its position clear that drone strikes constituted a violation of Pakistan`s sovereignty and violated international humanitarian lawsbesides being counter-productive to it efforts to bring peace and stability to the country and the region.

The government, according to the announcement, has decided to instruct Pakistan`s ambassadors in the capitals of the permanent member states of the UN Security Council to brief the host governments at an appropriate level on Pakistan`s concerns with specific reference to `the setback caused to the peace process initiative by the latest drone attack`.