The revelations came after the final round of talks between the representatives of the PTI and the PML-N government. Khan, who has been leading a massive protest against the Nawaz Sharif government over issues like corruption and rigging of elections, said he had rejected the offer, reported the Dawn.
However, a member of the PTI's negotiating team said the offer was made by one of the members of the government's side in a "casual" manner and nobody took it seriously.
A PML-N member had earlier advised the prime minister to appoint a deputy prime minister in consultation with the PTI which might have been the basis of Khan's claims, the report said.
Sources in the PTI said the offer was not a practical one for the PTI's main demand has been the resignation of the Sharif government.
The PTI has sought Sharif's ouster for a fair probe into the allegations that the general elections of 2013 were ragged.