Israel's ambassador to the UK has issued a swift apology after a junior embassy employee was secretly filmed saying he wanted to "take down" Foreign Office Minister Sir Alan Duncan.

In a statement, ambassador Mark Regev described the comments made by his political officer Shai Masot as "completely unacceptable".

Mr Masot had been covertly filmed making the comments at a London restaurant during a meeting with pro-Israel Tory activist Maria Strizzolo, an aide to Tory minister Robert Halfon, as well as an undercover reporter.

In a frank exchange Mr Masot asks Ms Strizzolo: "Can I give you the names of MPs I would suggest you take down?"

Ms Strizzolo then insists all MPs have "something they're trying to hide".

It is then that Mr Masot claims: "she knows which MPs I want to take down" before adding: "the deputy foreign minister."

A statement by the Israeli embassy following the revelations, which emerged after an investigation by Qatari-based TV channel Al Jazeera, said:"The Embassy of Israel rejects the remarks concerning Minister Duncan, which are completely unacceptable.

"The comments were made by a junior embassy employee who is not an Israeli diplomat and who will be ending his term of employment with the embassy shortly."

Ambassador Regev was revealed to have spoken with Sir Alan on Friday where he "made clear that the embassy considered the remarks to be completely unacceptable".

Lord Stuart Polak, director of Conservative Friends of Israel, said: "We utterly condemn any attempt to undermine Sir Alan, or any minister, or any Member of Parliament."

Sir Alan has been a strong critic of Israeli government settlement policy which he once described as an "act of theft".

During his recorded conversation Mr Masot suggests Mr Duncan is "impossible to rebuff.. he has a lot of friends".

Mr Regev's aide also suggests Foreign Secretary Boris Johnson is "basically good".

He adds of Mr Johnson: "He just doesn't care. He is an idiot but has become minister of foreign affairs without any responsibilities. If something real happened it won't be his fault... it will be Alan Duncan."

In a further discussion Mr Masot also refers to Tory MP Crispin Blunt, also a critic of Israel.

Ms Strizzolo says: "On the hit list? Yeah!" To which Mr Masot replies: "Arab apologists".

Mr Blunt, who is chairman of the Foreign Affairs Select Committee chairman, said the "apparent activity of a diplomat of a foreign state", in reference to Mr Masot, was "formally outrageous and deserving of investigation".

Ms Strizzolo said her conversation with Mr Masot was "tongue in cheek and gossipy".

In separate footage, Mr Masot is seen telling senior Labour MP and Labour Friends of Israel chief Joan Ryan that he has obtained "more than £1 million" to pay for sympathetic MPs from the party to visit Israel.

Mr Masot brags: "I have got it from Israel. It is an approval."

Ms Ryan says: "I didn't think you had it in your bag!"

The Mail on Sunday said the money would be used to send a delegation of LFI activists to Israel, a claim Ms Ryan dismissed as "rubbish".

An LFI spokesperson said: "The allegations in the Mail on Sunday story concerning LFI are not only totally untrue, they are utterly ridiculous. This conversation was about a visit openly  arranged, advertised by and paid for by the Israeli Embassy. It had nothing whatsoever to do with LFI delegations”

The Labour Party called for an inquiry into the incident, calling it a “national security issue”.

Emily Thornberry, the Shadow Foreign Secretary, said the footage revealed an “improper interference in our democratic politics”, which she described as “extremely disturbing”.

“It is simply not good enough for the Foreign Office to say the matter is closed. This is a national security issue.

“The embassy official involved should be withdrawn, and the government should launch an immediate inquiry into the extent of this improper interference and demand from the Israeli government that it be brought to an end.”