It remains unclear, however, if Baradar will agree to meet the Afghan delegation.
The Taliban have so far refused to talk directly with Karzai, his government or its representatives. Attempts to open talks between Afghanistan and the Taliban in June ended in failure after Karzai accused the militants of setting up a government in exile and demanded they remove their flag and a sign identifying the movement as the Islamic Emirate of Afghanistan. The Taliban refused and closed their office in the Gulf state of Qatar.
Baradar's whereabouts have not been known since his release and he has not met with members of his family or representative of the Afghan government or the Taliban. He is thought to be in a Pakistani government "safe house" that is constantly under guard.
Karzai hopes that Baradar can help kick-start negotiations to end the 12-year war. Along with Taliban leader Mullah Mohammed Omar, Baradar was a founding member of the Islamic militant movement.
One senior Taliban official told The Associated Press recently that Baradar is still under house arrest in Pakistan and is not allowed to see his family until he agrees to meet with the High Peace Council, which was set up by Karzai to negotiate with the religious movement.
The Taliban official told the AP in a telephone interview that Baradar had spoken twice to his family in Karachi since his release was announced Sept. 21.
Speaking on condition of anonymity because Mullah Omar has not authorized interviews, the official, who held a commanding position during the Taliban rule, also spent four years in Pakistani custody. He said Baradar met Taliban members while in custody and assured them that he would not defy Mullah Omar's orders forbidding direct talks with the Afghan government.
During the London meeting, the announcement said that Sharif accepted an invitation from Karzai to visit Kabul in coming weeks and that their interior ministers will also meet to discuss border security.
Relations between the two neighbors have been tense for years, with Afghanistan accusing Pakistan of supporting the Taliban insurgency and allowing the insurgents to retain safe havens in its tribal regions along the frontier. Pakistan has charged that Afghanistan allows insurgents opposed to Islamabad's government to use sanctuaries on its side of the border.
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AP Special Regional Correspondent for Afghanistan and Pakistan Kathy Gannon contributed to this report.
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