An anti-Islam Dutch politician banned from entering Great Britain was sent back to the Netherlands after he traveled to the U.K. anyway.

Upon Geert Wilders' arrival at Heathrow Airport, he was presented with a letter from Britain's Home Office saying that his opinions "threatenen community security." The right-wing lawmaker had been invited by a member of Parliament to show his anti-Islam movie "Fitna," which calls the Koran a "fascist" book and accuses Islam of being a violent religion.

On Wednesday, Wilders dared the "weak and cowardly" British government to arrest him when he got there.

He criticized the travel ban as an attempt to stifle freedom of speech and traveled to Britain on a point of principle.

Wilders told the AP by telephone it was "a sad day for Britain and freedom of speech."

"You would expect something like this to happen in Zimbabwe or Jordan," he said.

British Foreign Secretary David Miliband told the BBC that Wilders was guilty of "extreme anti-Muslim hate."

Wilders was told by the British Embassy in a letter Tuesday that he could not set foot in the country.

• Click here to read the letter from the British Embassy.

Britain's Home Office would not comment specifically on the ban, but it said it "opposes extremism in all its forms" and would work to "stop those who want to spread extremism, hatred and violent messages in our communities from coming to our country."

The U.K.'s Lord Malcolm Pearson, who invited Wilders to Britain, told the Daily Mail newspaper that the screening of the film would go ahead Thursday "with or without Mr. Wilders."

Click here to read more on this story from the Daily Mail.

Click here to watch 'Fitna.'

The Associated Press contributed to this report.