Jewish American singer Matisyahu confirmed his participation in a Spanish music festival on Friday two days after organisers apologised for cancelling his appearance following an uproar by pro-Palestinian groups.

The decision by the Rototom SunSplash festival to pull Matisyahu, who fuses reggae and hip-hop with Jewish influences, from its line-up was criticised by Jewish groups, the Spanish government and by the US and Israeli embassies in Spain.

The incident occurred after a local branch of the pro-Palestinian Boycott, Divestment and Sanctions (BDS) movement accused the 36-year-old of being a "Zionist" who supports the practice of "apartheid and ethnic cleansing".

When Matisyahu did not reply to festival organisers' questions about whether he was in favour of a Palestinian state, they cancelled his appearance in a decision denounced by the Spanish government.

On Wednesday, festival organisers backtracked and apologised to the singer, reinviting him to perform at the weeklong festival -- one of Europe's largest reggae festivals which is held in Benicassim in eastern Spain.

"Rototom SunSplash admits that it made a mistake, due to... the campaign of pressure, coercion and threats employed by the BDS Pais Valencia which made it think that the normal functioning of the festival could be threatened," organisers said in a statement on Wednesday.

Matisyahu, who had initially denounced the cancellation as "appalling" on Facebook, accepted the new invitation, a statement from the organisers said on Friday.

"Matisyahu has confirmed his participation in the 22nd annual Rototom SunSplash festival and will perform on the main stage on Saturday as originally planned," it said.