Three of Britain’s best-known Jewish authors have said they are concerned that anti-Zionism in the Labour Party is becoming “indistinguishable” from antisemitism.

Howard Jacobson, Simon Sebag Montefiore and Simon Schama posted an open letter in The Times in which they said they were “troubled by the tone and direction of debate about Israel and Zionism within the Labour Party”.

In the centenary year of the Balfour Declaration, in which the British government committed its support to establish a Jewish homeland in Palestine, the trio say: “Zionism is the right of the Jewish people to self-determination. We believe that anti-Zionism, with its antisemitic characteristics, has no place in a civil society.”

In 2009, Booker Prize winner Jacobson, now 75, wrote that criticism of Israel was “a desire to word a country out of existence,” and this week he again equated criticism of Israel with the will to destroy it.

“We do not object to fair criticism of Israel governments,” the three wrote, “but this has grown to be indistinguishable from a demonisation of Zionism itself – the right of the Jewish people to a homeland, and the very existence of a Jewish state.”

They said Jewish conspiracy theories had resurfaced along with “the promotion of vicious, fictitious parallels with genocide and Nazism,” adding: “How, in such instances, is anti-Zionism distinguishable from antisemitism?”

Adding their voice to a growing debate about anti-Zionism and antisemitism, the authors also allege that anti-Zionists “claim innocence of any antisemitic intent” but “frequently borrow the libels of classical Jew-hating”.

Turning their combined attention to Labour, they say “such themes and language have become widespread in Jeremy Corbyn’s Labour Party… so far the Labour leadership’s reaction has been derisory. It is not enough to denounce all racisms”.