"We want to repeat our stance once again that until the occupation of foreign troops ends, until Taliban names are removed from international blacklists and until our detainees are released, talks will yield no results," it said.
The statement comes as direct face-to-face talks between the militant group and the Kabul government were expected to start in Islamabad this week.
"We unequivocally state that the esteemed leader of Islamic Emirate (Taliban) has not authorised anyone to participate in this meeting and neither has the Leadership Council of Islamic Emirate decided to partake in it," the statement added.
Delegates from the four countries met in Kabul late February for a fourth round of talks aimed at reviving the nascent peace process, which stalled last summer.
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The quartet had called for a direct dialogue between the Taliban and Kabul by this week, a deadline that analysts called "completely unrealistic".
Kabul has repeatedly called for all Taliban groups to sit at the negotiating table though President Ashraf Ghani has said his government will not make peace with those who kill civilians.