Five ex-Labour employees are preparing to launch a libel claim against the party over its response to a Panorama programme about anti-Semitism.

Labour is set to be served with legal papers in the coming weeks for allegedly breaching its commitment to protect the rights of whistleblowers.

The claimants also allege the response to the programme from Labour figures including Jeremy Corbyn, Jon Lansman and Seumas Milne defamed them.

The move comes after a police investigation was launched into an anti-Semitic banner that was put outside Labour's annual conference in Brighton on Sunday.

The banner's cartoon depicts Labour leader Jeremy Corbyn gesturing at a podium that bears the Palestinian flag and the writing: “Palestinian Rights”.

Behind him, a man bearing similarity to Israeli Prime Minister Benjamin Netanyahu can be seen in a blue jet emblazoned with a Star of David and the words: “The Lobby”, as it releases a missile with the word “defamation” written across it.