Imran Khan, the former Pakistan cricket captain turned politician, was taken off an international flight from Canada to New York and questioned by US immigration officials over his views on drone strikes and jihad.

Khan, who has been at the forefront of a high-profile campaign as leader of the Pakistan Movement for Justice party (PTI) to end US drone strikes in northern Pakistan, had been in Canada to give a speech and was on his way to a fundraising dinner in the US on Friday.

Khan recently attempted to lead a high-profile march into south Waziristan which included US peace activists from the Code Pink group with some 15,000 of his supporters.

He claims that the drone strikes kill large numbers of innocent civilians – a claim denied by the US.

“I was taken off from plane and interrogated by US Immigration in Canada on my views on drones. My stance is known. Drone attacks must stop,” Khan tweeted yesterday after his questioning.

He added: “Missed flight and sad to miss the fundraising lunch in NY but nothing will change my stance.”

A US state department spokeswoman confirmed Khan’s questioning. “We are aware that Imran Khan was briefly delayed in Toronto before boarding the next flight to the United States,” she told Pakistani media.

“The issue was resolved. Mr Khan is welcome in the United States.”

US immigration authorities refused to comment on Khan’s case but a spokeswoman quoted by the Toronto Sun newspaper said: “Our dual mission is to facilitate travel in the United States while we secure our borders, our people, and our visitors from those that would do us harm like terrorists and terrorist weapons, criminals, and contraband,” said CBP spokesman Joanne Ferreira.

“Under US immigration law, applicants for admission bear the burden of proof to establish that they are clearly eligible to enter the United States. In order to demonstrate that they are admissible, the applicant must overcome all grounds of inadmissibility.”

Some Canadian commentators have speculated that Khan’s questioning was because of groups who have been protesting his visit to the US, including a group called the American Islamic Leadership Coalition which reportedly wrote to US secretary of state Hillary Clinton asking her to revoke the US visa granted to Khan.

“The US embassy made a significant error in granting this Islamist leader a visa,” the group said in a statement.

“Granting individuals like Khan access to the US to fundraise is against the interest of the people of Pakistan and the national security interests of the US.”

Ali Zaidi, an official in Khan’s party demanded “a prompt and thorough inquiry into this sordid episode” and “an unconditional apology from the US government”.