A string of iconic figures from Europe's far-right movement have been detained by UK border police hours before they were due to speak at an anti-Islam rally in Birmingham, organisers have said.

The group was due to march with Britain First activists through the city on Saturday (24 June), in a sign of the growing links between British "extremists" and nationalists abroad.

But Polish Catholic priest Jacek Miedlar – branded a "fanatical hate preacher" by anti-racism campaigners in Poland – and fellow anti-Islam activist Piotr Rybak – once convicted for burning an effigy of a Jew – were both detained by border police after landing at Luton Airport on Saturday morning.

At around the same time, Dutch national Edwin Wagensveld, who is head of his country's branch of anti-Islam movement Pegida, was also held at Birmingham airport, Britain First told IBTimes UK.

All three figures were due to speak at the Birmingham rally.

It comes after anti-extremism campaigners in both Poland and the UK had warned of their visits to Britain, accusing them of spreading Islamophobia and anti-Semitism.

Miedlar, who is currently suspended by his local Catholic church for his firebrand nationalist sermons, has addressed tens of thousands people at right-wing revival rallies in Poland.

His critics accuse him of using radical sermon-like speeches to spread anti-Semitism, homophobia and anti-Muslim sentiment.

In February, he was denied entry to the UK hours before he was due to speak at another Britain First rally in Telford on suspicion of hate speech offences.

After being forced to return to Poland he blamed the "Jewish secret service".

"Miedlar is a radical nationalist on every front: anti-gay, anti-Muslim and anti-Semitic," Rafal Pankowski, a professor at Warsaw's Collegium Civitas and director of Poland's Never Again anti-racism group, told IBTimes UK.

Accusing Rybak of being a "symbol of violent extremism", Prof Pankowski said the pair's aim is to radicalise young Poles living in Britain against Muslim communities.

"Both Miedlar and Rybak are very well known for their intensity in their message of hate ... The idea is to create as much tension between communities in the UK as they can," he said.

Britain First's anti-Islam protest in Birmingham, where police said fewer than 200 people are expected to attend, comes in the wake of terrorist attacks in London and Manchester.

The far-right party describes itself as "committed to maintaining and strengthening Christianity as the foundation of our society and culture" and repeatedly warns its followers of a coming "civil war" with Islam.

Its activists are notorious for what critics call "provocative" street-level action in areas of the UK that are home to large Muslim communities, including so-called "mosque invasions" and "Christian patrols".

Deputy leader of the party, Jayda Fransen, condemned the detention of Miedlar, Rybak and Wagensveld by border authorities, calling it "illegal".

"They have not committed any crime – it's completely ridiculous," she told IBTimes UK.

In the wake of Monday's attack outside a mosque in Finsbury Park, anti-extremism group Hope Not Hate accused Britain First and other prominent anti-Islam activists of having fueled "a climate of hate" against Muslims.