The Israeli ambassador in London has apologized after a member of his staff was caught on camera saying he wanted to "take down" British Foreign Office Minister Alan Duncan, a high-profile UK government supporter of a Palestinian state.

Shai Masot, a senior political officer at the embassy, was secretly filmed discussing British lawmakers by broadcaster Al Jazeera. The footage was obtained by the Mail on Sunday.

"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," a spokesman said in a statement.

Masot was talking to Maria Strizzolo, who was previously an aide to another minister, and an undercover reporter, the Mail on Sunday said.

He said Strizzolo knew "what MPs (lawmakers) I want to take down".

"Can I give you some MPs (lawmakers) that I would suggest you would take down?," he said to her.

When pressed on who he meant, he said: "The deputy foreign minister."

He didn't specify what he meant by "take down", although in the context of the conversation it could describe engineering a political downfall.

He also discussed British Foreign Minister Boris Johnson, saying he was "solid" on Israel, but adding: "You know he is an idiot?"

The embassy said Ambassador Mark Regev had spoken to Duncan on Friday, apologized for the comments and made clear that the embassy considered the remarks to be completely unacceptable.

A spokesman for the British Foreign office confirmed the Israeli ambassador had apologized, and said it was clear the comments did not reflect the views of the embassy or the government of Israel.

"The UK has a strong relationship with Israel and we consider the matter closed," the spokesman said.