"We are still waiting for an answer and confirmation from the Board of Control for Cricket in India. It is clear that this matter is now in the hands of the Indian Prime Minister Narendra Modi and he will give clearance for the series," Khan told reporters in Lahore.
Khan, however, admitted that time was running out for having the series. "We are preparing to work round the clock to have this series but it is also something the Indians now need to think about," he said.
The PCB and BCCI have in principle agreed to have a short limited-overs series in Sri Lanka from mid-December with the series being treated as a home series for Pakistan.
But while Pakistan Prime Minister Nawaz Sharif has given clearance to have the series, the BCCI has said they are still waiting for clearance from their government.
Pakistan's head coach Waqar Younis when asked whether he thought the Pakistan team, after its recent defeats to England, was prepared for the series against India, said he would like to see the matches happening.
"I think Pakistan and India need to play more against each other. As far as performances is concerned India is also doing well in Test cricket like we have done but they have also struggled like us in the limited over matches," he noted.
"So it would be an interesting series for both teams. But we are prepared to play whenever the Boards give the go-ahead," he said.