Washington: Pakistan's powerful spy agency ISI provided information to the CIA which helped the US track down and kill al-Qaeda chief Osama bin Laden, Prime Minister Imran Khan said Monday in a significant revelation as Islamabad had so far denied having any knowledge of the terror chief until he was shot dead in 2011.

Khan, who is visiting Washington on his maiden official trip, revealed this during an interview with Fox News when he was asked whether his country would release jailed Pakistani surgeon Shakeel Afridi who helped the CIA track down Osama.

Khan's statement is significant because Pakistan had so far denied that it had any information about the hideout of Osama before he was killed in a covert raid by a US Navy SEAL team in Abbottabad, a garrison town north of Islamabad, on May 2, 2011.

"It was ISI that gave the information which led to the location of Osama bin Laden. If you ask CIA it was ISI which gave the initial location through the phone connection," Khan said.

Responding to questions, Khan was reluctant to give any commitment on the release of Pakistani doctor Afridi. US President Donald Trump is seeking his release.

Khan said that the release of Afridi is an "emotive issue" for Pakistan as in Pakistan he is considered a spy for the US.

We in Pakistan always felt that we were an ally of the US and if we had been given the information about Osama, we should have taken him out, he said.

Khan said that Pakistan was fighting the war against terrorism for the US. The raid and killing of Osama, he said "hugely embarrassed Pakistan".

Here we were an ally of the US and the US did not trust us. And they actually came and bombed and killed a man in our territory, Khan said. When pointed out that Osama was not just a man, but a terrorist who killed more than 3,000 Americans, Khan said that Pakistan lost 70,000 people in this fight.

We were fighting this war for the US and we lost all these people fighting this war. So there was obviously a lot of anger about the way this whole thing was done. But you know, that's all in the past, Khan said.

When the interviewer asked, You are the prime minister, you can make a decision catch.," Khan said, There's some decisions that are democracy which even a prime minister finds it difficult, because we do have an opposition. But this is something that can be negotiated over time."

Khan said he would be willing to consider releasing Afridi in exchange for Pakistani neuroscientist Aafia Siddiqui, who is serving an 86-year US prison sentence after her 2010 conviction of shooting at FBI agents and soldiers.

So, we could negotiate some sort of swap, Khan said, adding that this was not talked about during his meeting with President Trump in the White House.

The negotiations for swap of Afridi and Siddiqui could take place in the future, he said. We can negotiate. I mean, no negotiations have started, Khan said.

Khan also said he felt humiliated when the US forces killed the dreaded terrorist Osama bin Laden in a daring strike inside Pakistan in 2011.

Speaking at the US Institute of Peace (USIP) here, Khan said the US did not trust Pakistan over the issue of Osama bin Laden.

"I can tell you as a Pakistani, never did I feel more humiliated when Osama bin Laden was taken out in Pakistan by the US troops, Khan said.

"Never did I feel more humiliated because here was a country which was supposed to be an ally and our ally did not trust us, Khan said in response to a question.

Khan said he wants to have a relationship of friendship with the US.

"For every Pakistani, it was humiliating. We never want to be in that same position again. We want to have a relationship of friendship. It doesn't matter, a friend can be rich and the other can be not be so rich. So it's about a dignified relationship and that's what I hope, he said.