ISLAMABAD, Pakistan — Pakistani government representatives failed to appear on Tuesday for the scheduled start of peace talks with the Taliban, forcing the postponement of the talks and drawing a sharp rebuke from the militants’ representatives.

The episode added to the swirl of contradictory statements, confusion and delays that have surrounded the peace initiative since last week, when Prime Minister Nawaz Sharif made the surprise announcement that a four-member delegation would hold talks with the Pakistani Taliban.

In turn, the Taliban named five public figures, including the opposition politician Imran Khan, to represent them in the talks. But Mr. Khan and another of the five refused to do so.

The three remaining designees, led by Maulana Sami ul-Haq, a prominent religious scholar with close ties to Taliban leaders, said on Monday that they would meet the next day with the government representatives in Islamabad, the capital.