BARCELONA — A small cluster of protesters failed to disrupt an Israeli singer at a concert in Barcelona.

Noa, also known as Achinoam Nini, performed a Catalan hymn on Friday at Catalan Day celebrations, backed by the Arab Orchestra of Barcelona.

The reception for the singer was enthusiastic, overwhelming a small group of about 50 anti-Israel activists who stood up and began blowing whistles, waving Palestinian scarves and flags, as well as signs saying “Boycott Israel.”

A number of small left-wing parties and groups had called for her removal from the program unless she retracted her statement during last winter’s Gaza  war against Hamas. In an open letter to the Palestinian people last January, Noa said: “I can only wish for you that Israel will do the job we all know needs to be done, and finally rid you of this cancer, this virus, this monster called fanaticism, today, called Hamas.”

Catalan politicians had defended Noa, who has a large following in Europe and particularly in Spain. Josep-Lluis Carod-Rovera, the vice-president of the Catalan parliament, likened those calling for the boycott to Iranian anti-Semites.

Noa promotes Jewish-Arab dialogue; she represented Israel together with an Israeli Arab singer in this year’s Eurovision song contest.