London Mayor Sadiq Khan — who wants the U.K. to cancel Donald Trump's upcoming state visit because the president's "policies go against everything we stand for" — once tried to overturn Britain's ban on Nation of Islam leader Louis Farrakhan.

It's one of a number of ironies in the latest dispute between Trump and London's Muslim mayor, which began with Trump's tweet Sunday criticizing Khan for saying after the London Bridge attack that there is “no reason to be alarmed.” Khan, in context, was referring to the increased police presence in London in response to the attack Saturday night in which eight people were killed rather than the attack itself. But Trump insisted, nevertheless, the mayor, who has said terror attacks are “part and parcel of living in a big city,” was downplaying the significance of terrorism.

In any case, Khan's suggestion that the British government cancel Trump's planned visit — no date has been set — apparently is not based merely on the contentious Twitter exchange.

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It's the U.S. president's policies that should disqualify him from entry to the U.K., Khan explained in an interview with Britain's Channel 4 News.

Asked whether the visit should be called off, Khan said the U.K. should not be “rolling out the red carpet to the president of the USA in the circumstances where his policies go against everything we stand for."

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Khan reacted in January to President Trump's executive order putting a moratorium on travel and migration from select, terror-producing, Muslim-majority countries, calling it a "targeting" of people for their faith that is "cruel, prejudiced and counterproductive." Trump has argued the pause in travel is needed to give time to ensure a proper vetting system is in place to prevent terrorism.

In January, the British Parliament debated banning Trump from entering the U.K. shortly before his inauguration as president. A Muslim Labour Party member of Parliament said Trump's "words are poisonous," charging they "risk inflaming tension between vulnerable communities."

The same charge, without any evidence, was leveled at talk host Michael Savage when he was banned from entering the U.K. in 2009. Government correspondence by top officials revealed the decision was made in an attempt to provide “balance” to a “least wanted” list dominated by Muslim extremists. The ban remains in place eight years later, and a new petition drive is asking Trump and the U.S. State Department to intervene and urge the U.K. to drop it.

'Sketchy connections'

Counter-terror expert Jim Hanson said in a Fox News interview it probably was a mistake for Trump to criticize Khan for the "alarm" comment, but he pointed out the mayor "has had some very sketchy connections."

Hanson, executive vice president of the Center for Security Policy, noted Khan has publicly supported Muslim Brotherhood scholar Yusuf al-Qaradawi and said the July 2005 London subway attack in which 52 people died was caused by British foreign policy.

"So, I think if the president sticks to legitimate criticisms of Mayor Khan, perhaps he can push him in the right direction," Hanson said.

In 2001, Khan represented Farrakhan after the U.K. government banned the Nation of Islam leader's entry into the country, citing Farrakhan's anti-Semitic and racially divisive views. Khan was successful at overturning the government's ban in the High Court, but the government subsequently won on appeal.

Khan and his firm also consulted on the defense of Zacarias Moussaoui, known as the potential "20th" 9/11 hijacker.

During the mayoral election, Khan told London's Jewish News that his past job as a human rights lawyer meant he "had to speak on behalf of some very unsavory individuals."

In his defense of Farrakhan, Khan insisted "there was no evidence at all" that Farrakhan's visits to other parts of the world had caused the kind of anti-Semitic and racially divisive problems that the British government feared Farrakhan would provoke.

A British High Court judge lifted the ban on Farrakhan but his ruling was overturned on appeal.

When Khan visited Chicago last year to give a speech arguing for progressive, anti-extremist global policies at the Chicago Council on Global Affairs, the Farrakhan issue came up.

During Khan's successful campaign to win election May 5 and become London's first Muslim mayor, opponent Zac Goldsmith and his Conservative Party allies, including former Prime Minister David Cameron, highlighted Khan's links to radical Muslims, the London Guardian reported

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Cameron claimed Khan was close to south London cleric Suliman Gani, a supporter of ISIS, who until 2013 was imam of Tooting Islamic Centre in Khan’s constituency. Gani appeared at an event last November, on the night of the Paris terror attacks, in which speakers called on British Muslims to struggle for an Islamic state.

Qaradawi: Holocaust 'divine punishment'

In 2004, Khan spoke up for Qaradawi at a time when Khan was chairman of the legal affairs committee of the Muslim Council of Britain.

Qaradawi, who was banned in 1999 from entering the U.S. and in 2008 from entering the U.K., has said: “Oh Allah, deal with your enemies, the enemies of Islam. Oh Allah, deal with the usurpers and oppressors and tyrannical Jews. Oh Allah, deal with the plotters and rancorous crusaders.”

Asked for his response, Khan said he couldn't comment on the specific quote but insisted there is "consensus among Islamic scholars that Mr. al-Qaradawi is not the extremist that he is painted as being by selective quotations from his remarks.”

Qaradawi, however, has cited other Islamic texts calling for the killing of Jews and said Hitler's Holocaust was "divine punishment."

He has endorsed Palestinian suicide bombings, according to the Investigative Project on Terrorism, and in a 2007 interview said it is "obligatory on all Muslims to resist any possible attack the U.S. might launch against Iran."

"The U.S. is an enemy of Islam that has already declared war on Islam under the disguise of war on terrorism and provides Israel with unlimited support," he said, according to Discover the Networks.

Qaradawi is chairman of the IslamOnline website, which has published numerous anti-Semitic and anti-Israel Islamic rulings and is supportive of violence against non-Muslims.

He was one of the largest shareholders in Al Taqwa Bank, which the U.S. Treasury Department designated as a terrorist financier with ties to al-Qaida in 2001.

During the campaign, Khan's opponent Goldsmith accused him of attending a rally in 2006 in Trafalgar Square against the publication of cartoons of the prophet Muhammad. At the rally, Azzam Tamimi, a radical cleric, threatened “fire throughout the world” if cartoonists did not stop.

Khan said later: “Speakers can get carried away but they are just flowery words.”

Goldsmith’s team also cited Tamimi as saying that after Israel is destroyed and replaced with an Islamic state, Jews should “sail on the sea in ships back to where they came or drown in it."

A Khan spokesman said: "That is obviously an extremist statement. Sadiq wouldn’t have been aware of who Tamimi was at the time."

British Prime Minister Theresa May told the London Sun Tuesday Trump was "wrong" to criticize Khan.

"The relationship with America is our deepest and most important defense and security relationship," May said. "Having said that, I think Donald Trump is wrong in what he said about Sadiq Khan, in relation to the attack on London bridge."

Washington Examiner columnist Tom Rogan contended Khan's call on Britons to stay ''calm and vigilant'' was "a case of transatlantic lost-in-translation."

In the United States, a politician who tells citizens to ''keep calm'' in the aftermath of a terrorist attack would be regarded as delusional, he wrote, while in Britain is a point of deep pride reaching back to the Nazi bombing raids from 1940-1941 in which tens of thousands of British civilians were killed.

In another tweet Sunday, however, Trump made his point clear.

"We must stop being politically correct," the president wrote, "and get down to the business of security for our people."

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