A Muslim Gold Star father who famously offered to lend Donald Trump his copy of the U.S. Constitution has cancelled a scheduled speech in Toronto because “his travel privileges are being reviewed,” according to the event organizer.

Ramsay Talks, which arranged for Khizr Khan to speak in Toronto on Tuesday, said in a Facebook post that Khan was notified Sunday night about the travel review.

Ramsay Talks says in its statement that Khan has been a U.S. citizen for more than 30 years and his speech would have been about “tolerance, understanding, unity and the rule of law.”

According to the organizer, Khan said that “this turn of events is not just of deep concern to me but to all my fellow Americans who cherish our freedom to travel abroad.”

Khan told CTV News Monday afternoon that he has “no comments at this time.”

An advertisement from Ramsay Talks had stated that Khan’s speech would be about “the appalling turn of events in Washington – that we don’t all end up sacrificing everything.”

Khan’s son, Capt. Humayun Khan, was killed by a suicide bomber in Iraq in 2004.

He gave a speech at the Democratic National Convention, where Hillary Clinton was nominated for president last July, in which he argued that then-Republican candidate Donald Trump’s promised Muslim ban was immoral and unconstitutional.

“Have you ever been to Arlington Cemetery?” Khan told a crowd in Philadelphia. “Go look at the graves of brave patriots who died defending the United States of America. You will see all faiths, genders, and ethnicities. You have sacrificed nothing—and no one,” he said.

Khan then offered to lend Trump his copy of the U.S. Constitution so that he could “look for the words liberty and equal protection of law.”

Trump imposed a ban on people from seven predominantly Muslim nations on Jan. 27. The ban was suspended by a court, but a new executive order was issued Monday that bans people from six nations that Trump argues pose a security threat.

Khan immigrated to the United States from Pakistan, which is not one of the countries listed in Trump’s travel ban order. The countries named in the executive order are Iran, Syria, Somalia, Sudan, Yemen and Libya.