Khan, head of the Pakistani Tehreek-e-Insaf party, has been criticized for calling for peace talks with militants as scores of people have been killed in recent attacks, the British newspaper The Guardian reported Thursday.
Last month, Khan called for unconditional talks with militants, whom he referred to as "stakeholders."
In response, the Taliban set pre-conditions for talks, calling for a government ceasefire, withdrawal of Pakistani troops from tribal areas along the Afghanistan border and an end to drone strikes.
Khan has now changed his stance toward dialogue without condition. He says the Taliban will have to accept the constitution, end sectarian violence and disarm.
Whether the Taliban and similar groups accept such conditions could decide if Khan moves toward military action.
"It could be just a complete deadlock, a collapse, with [the Taliban] insisting on demands that we cannot meet," he said. "I reckon you will know in two months."
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