It is Karzai’s first visit to Islamabad in 18 months and signals a desire by both countries to overcome distrust and hostility as 87,000 North Atlantic Treaty Organization combat troops prepare to leave Afghanistan next year.
The visit began with an out-of-tune rendition of both national anthems by a Pakistani military band, before Karzai inspected an honour guard and swept into talks with Nawaz Sharif.
It is his first meeting with the new prime minister, who took office in June after winning elections.
Kabul announced that he would hold a separate meeting with Pakistani President Mamnoon Hussain even though Hussain only formally takes office on September 9.
No mention was made of outgoing President Asif Ali Zardari, whose summit with Karzai in Britain in February briefly revived hopes of a rapprochement that quickly unravelled in a series of public rows.
Elements of the Pakistani state are widely accused of funding, controlling and sheltering the Taliban, but Islamabad says publicly it will do anything to stop the fighting in Afghanistan.
Karzai was furious when the Taliban opened a liaison office in Qatar in June. It was billed as a precursor to talks with United States officials but perceived as a self-styled embassy for a government in waiting.
But he is now expected to ask Pakistan to help open a direct channel of communication with the militants.
Karzai insists that his government should take a central role in any peace talks, but the Taliban refuse to open contact with him or his appointed negotiators, dismissing him as a US puppet.
“The first item with Pakistan will be the peace negotiations,” Karzai told a news conference in Kabul on Saturday.
He praised Sharif for having “all the right intentions for stability and peace,” but conceded that previous visits had not achieved the goal of improving security in Afghanistan.
Karzai believes Taliban safe havens in Pakistan are the main cause of increased violence in his country.
“I will travel to Pakistan hoping to get a result out of it. I’m hopeful, but not sure, I will only go with hopes, and wish they materialize,” he told reporters.
Afghan government peace negotiators accompanying Karzai have called for the release of the most senior Taliban figure detained in Pakistan, former deputy leader Abdul Ghani Baradar.
Pakistan released 26 Taliban prisoners late last year, including the militants’ former justice minister Nooruddin Turabi.
Afghan officials believe the releases can encourage former detainees to talk to the Kabul government, although observers say there is little evidence those hopes have been realized. Several prisoners are also understood to have returned to the battlefield.