REUTERS - An American Jewish musician who was controversially barred from a reggae festival in Spain before being invited back to play performed to catcalls from some pro-Palestinian protesters on Sunday, though the concert passed off peacefully after a tense build-up.

Matisyahu, who fuses reggae, hip-hop and rock with Jewish influences in his songs, was uninvited from the Rototom Sunsplash festival last week when he failed to reply to a demand to clarify his position on Palestinian statehood.

Organizers were forced into a U-turn after an outcry, with the Spanish government and Jewish organizations condemning the decision, and invited the artist to play on the last night of the week-long festival.

Open gallery view Revellers dance during a concert of Jewish American singer Matisyahu at Rototom Sunsplash Reggae festival. August 22, 2015. Credit: AFP

Amid a packed audience at the event in Benicassim, near Valencia in eastern Spain, dozens of people whistled in disapproval as Matisyahu took to the stage in the early hours of Sunday, with some waving Palestinian flags and chanting "out, out".

But many others in the audience of hundreds applauded the musician as the concert got under way.

"Whoever you are and wherever you come from raise a flag and wave it in the air," Matisyahu called to the crowd before his closing song. "Let music be your flag," he added, after dancing his way through his 45-minute set.

Matisyahu, whose real name is Matthew Miller, earlier this week condemned the attempt to "coerce (him) into political statements" and said politics played no part in his music.

The campaign to eject Matisyahu was led by the Valencia branch of the BDS group, which opposes Israel's occupation of Palestinian territories and campaigns against groups and individuals over their links to Israel.

It had urged a boycott of the American Jewish musician after objecting to comments he had previously made, including in an interview where they said he had questioned the existence of a country called Palestine.