US envoy James Dobbins arrived in Islamabad on Tuesday for talks with Prime Minister Nawaz Sharif and other senior officials on efforts to open peace talks with Afghan Taliban, the premier's office said.
Dobbins, who flew in from Kabul, met Sharif and briefed him on developments relating to Afghanistan, the office said in a statement.
"The Prime Minister conveyed to Ambassador Dobbins that Pakistan had the highest stakes in the return of peace and stability to Afghanistan," it said.
"He assured Mr. Dobbins of Pakistan's full commitment to an Afghan-led and Afghan-owned peace process and highlighted various steps Pakistan had taken in the regard," it said.
"Noting that the situation in Afghanistan had reached a crucial phase as the US proceeds with its drawdown, the prime minister stressed the need for Pakistan and the United States to remain closely engaged."
Other Pakistani officials said the meetings of Dobbins, the US special representative to Afghanistan and Pakistan, will focus on "efforts to promote an Afghan-led reconciliation process".
The US embassy in a statement said that Dobbins expressed "great appreciation" for the role Pakistan has played in supporting and helping advance the peace process, it said.
"Ambassador Dobbins reiterated the United States' commitment to working with the new democratically-elected government of Pakistan to build a strong, mutually beneficial bilateral relationship."
The Afghan Taliban opened an office in Qatar last Tuesday in a step towards talks as the US-led NATO combat mission prepares to leave Afghanistan in 2014 despite a resilient Taliban insurgency 12 years after they were ousted following the 9/11 attacks.
But Afghan President Hamid Karzai reacted furiously to the office being styled as a Taliban government-in-exile under the rebels' white flag and using the formal name of the "Islamic Emirate Of Afghanistan" from their hardline 1996-2001 regime.
Kabul, which says it is committed to the peace process, insisted that the Qatar office be used for only direct negotiations between the Taliban and the Afghan government.
Pakistani Taliban spokesman Ehsanullah Ehsan in a video released to media said the insurgents will follow any decision taken by Afghan Taliban leader Mullah Omar.
"Mullah Omar is our Amir (chief) and we will abide by any decision he takes regarding peace talks with America," Ehsan said.
In Kabul on Monday, Dobbins said Washington had been "outraged" at the manner in which the Taliban opened the office, saying it was "inconsistent" with assurances the United States had given and received.
Some experts have suggested that Pakistan likely played a key role in persuading a reluctant Taliban to consider tentative peace talks with its American and Afghan government foes.
Western capitals believe that Pakistan can play a crucial role in helping to get the Taliban to the negotiating table as it was one of only three countries to recognise its 1996-2001 regime in Kabul.