ISLAMABAD: Pakistan on Monday summoned the ambassador of United States, David Hale, to express concern over the US air strike inside Pakistani territory on Saturday, May 21 — which reportedly targeted Afghan Taliban chief Mullah Akhtar Mansour.

According to a statement released by the Foreign Office, Special Assistant to Prime Minister on Foreign Affairs Tariq Fatemi pointed out to the US envoy “the drone strike was a violation of Pakistan’s sovereignty and a breach of the United Nation’s Charter that guarantees the inviolability of the territorial integrity of its member states”.

Fatemi also emphasised that “such actions could adversely impact the ongoing efforts by the Quadrilateral Coordination Group (QCG) for facilitating peace talks between the Afghan Government and the Taliban”, read the statement.

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The special assistant further underlined that Pakistan and United States had been closely coordinating in the fight against the menace of terrorism and that this cooperation needed further strengthening.

US President Barack Obama had on Monday confirmed that Mullah Mansour was killed in a US air strike, hailing his death as an “important milestone” in efforts to bring peace to Afghanistan.

"We have removed the leader of an organisation that has continued to plot against and unleash attacks on American and Coalition forces, to wage war against the Afghan people, and align itself with extremist groups like Al Qaeda," the US president said in a statement.

"We will work on shared objectives with Pakistan, where terrorists that threaten all our nations must be denied safe haven," he said.