The BBC has been urged to drop Britain’s Eurovision entrant after it emerged he had signed a letter accusing Israel of genocide in Gaza.
Olly Alexander, 33, endorsed a statement by gay rights charity Voices4London “in solidarity with the Palestinian liberation movement”.
He signed an open letter in October criticising the country as an "apartheid regime" involved in "genocide".
Issued weeks after the October 7 attacks by Hamas, it made no mention of the Palestinian militants but claimed “current events simply are an escalation of the state of Israel's apartheid regime”.
Jewish charities want the ex-Years and Years singer replaced for May's contest in Sweden.
The BBC - which broadcasts and helps fund the annual contest in which Israel takes part - is facing calls to drop him.
A Conservative source told The Daily Telegraph: “Letting an openly anti-Israel singer compete on the same stage as Israel is either a massive oversight or sheer brass neck from the BBC.
“After they refused to call Hamas a terrorist organisation, you would think BBC bosses would try to steer clear of causing any more diplomatic blunders.”
The Campaign Against Antisemitism said the corporation "can and must" cut ties with Alexander.
Alexander was announced as the representative for the UK during the Strictly Come Dancing final on Saturday.
The letter added: "Queer and trans Palestinians have long highlighted that pinkwashing plays a significant role in Zionist propaganda. We stand against any and all harassment and discrimination against Jewish communities.
"For the many queer and anti-Zionist Jewish individuals invested in liberation, this unthinking philosemitism, which hesitates to criticise an ongoing genocide out of fear of being seen to criticise Jewish people, is simply the other face of anti-Semitism."
A spokesman for the Campaign Against Anti-Semitism said: "The rhetoric in this letter, which is seemingly endorsed by Olly Alexander, is extreme. It is appalling in particular that it condemns 'unthinking philosemitism'."
The Standard has approached Alexander's representatives for comment.
