Conveying US President Donald Trump's wishes, US Special Envoy for Afghan reconciliation Zalmay Khalilzad, who called on Khan on Wednesday, said the "US leadership looked forward to working with Pakistan in furthering the shared goal of peace through a political settlement in Afghanistan."

A statement issued by the Pakistan Prime Minister's Office said it was a "courtesy call".

Khan welcomed Trump's letter seeking cooperation in dealing with the issue in Afghanistan, along with the US' "assurance to work with Pakistan on this shared objective".

Earlier, the US has chided Pakistan and said it was time all nations supported the efforts of the United Nations, India and Afghanistan to help maintain peace in South Asia.

Responding to a question on US President Donald Trump's letter to Pakistan Prime Minister Imran Khan seeking his support in maintaining peace in Afghanistan, US Defence Secretary Jim Mattis said: "We're looking for every responsible nation to support peace in the sub-continent and across this war in Afghanistan that's gone on now for 40 years."

"It's time for everyone to get on board, support the United Nations; support Prime Minister Modi's, (Afghan) President (Ashraf) Ghani and all those who are trying to maintain peace and make for a better world here," he told a news conference at the Pantagon on Monday.

"We are on that track," he said. "We'll do our best to protect the Afghan people."