Leaders of two prominent Jewish organisations have signed a multi-faith letter of protest to Prime Minister David Cameron over a Bill to restrict political lobbying.

Rabbi Sybil Sheridan, the chairman of the Assembly of Reform Rabbis UK, and Paul Anticoni, chief executive of World Jewish Relief, say that the proposed legislation could have “unintended consequences” by hitting religious charities.

The Transparency of Lobbying, Non-Party Campaigning and Trade Union Administration Bill is intended to regulate lobbying in the run-up to elections, including reducing the amount of money that can be spent on campaigning.

The Jewish Leadership Council has already warned that it could have an adverse impact on Jewish groups wanting to promote the rights of shechitah or brit milah, for example.

Rabbi Sheridan and Mr Anticoni joined 11 other leaders from other faith-based groups, including the Methodist Conference, the Salvation Army, Islamic Relief and the Muslim Council of Britain.

Writing to Mr Cameron and Deputy PM Nick Clegg, the said that the Bill as currently worded, “may curtail our ability to express deeply-held beliefs in the political arena”.

They wrote: “We are concerned that this Bill does not adequately safeguard the activities of religious organisations and that there is a very real risk that non-biased political activity will be captured by the resultant Act”.