Government plans to investigate Muslim sharia courts will not include a review of the Jewish religious court system, the Board of Deputies has said.

Outlining Conservative Party plans to tackle extremism this week, Home Secretary Theresa May said there was a "problem" with the application of sharia law in some parts of Britain.

Mrs May said: "We know enough to know we have a problem, but we do not yet know the full extent."

Announcing plans for an independent investigation, she cited issues relating to divorce and the treatment of women under Islamic rulings.

But a Board spokesman dismissed fears that Jewish courts could also be considered for investigation, saying the Home Office had given assurances that there were no plans to review Batei Din.

"The government accepts the existence of sharia courts, just as it accepts Batei Din courts, but ministers want to make sure that the sharia courts are operating in accordance with the law.

"There is no evidence that Batei Din are working in a way that is incompatible with the law," the spokesman said.

But Mayor of London Boris Johnson suggested that he would ban Jewish religious courts along with sharia courts.

In a radio interview after Mrs May's announcement, he said he was opposed to "a sharia system running in parallel with UK justice… I won't have it in London".

Asked if Batei Din would also have to go, he said: "Yes, absolutely. Sauce for the goose is sauce for the gander."

Mrs May said that, if elected, a Tory government would use measures such as the closure of premises owned by extremists and special officers to tackle extremism in prisons.