The identity of Israel's next ambassador to the United Kingdom has become the latest bone of contention in the growing political feud between Prime Minister Benjamin Netanyahu and his foreign minister, Avigdor Lieberman.

The current ambassador, Ron Prosor, is poised to be appointed in the next few weeks as Israel's new ambassador to the United Nations.

The crucial post in New York has been vacant for the past six months since Professor Gavriella Shalev, an appointee of former Foreign Minister Tzipi Livni, returned to Israel. For now, the ambassador to Colombia, Meron Reuven, is filling in.

While the appointment of ambassadors is the prerogative of the foreign minister, the prime minister traditionally has a say regarding the more senior posts. Recently, Mr Netanyahu and Mr Lieberman have clashed over a range of foreign and domestic policy issues and the diplomatic posting is just the latest. The premier had been trying to persuade one of his closest allies, Environment Protection Minister Gilad Ardan, to become the next ambassador to the UN but last week Mr Ardan refused the job.

Since then, the leading candidate has been Mr Prosor, who has received wide acclaim for his three-year term in London, becoming the best known diplomat in Israel, due to the reports of his sparring with the British media. He is a career diplomat who served under a previous Likud government as director-general of the Foreign Ministry.

Arad to be ‘promoted out of the way’

Over the weekend, a senior source in the prime minister's office leaked to the Israeli media that Mr Netanyahu planned to move Mr Prosor to New York and replace him with his diplomatic adviser, chairman of Israel's National Security Council, Dr Uzi Arad.

Dr Arad, a former head of the Mossad research branch, is regarded as a brilliant maverick, but has also been the source of much tension between senior officials in the prime minister's circle and the higher echelons of Israel's security establishment. His proposed move to London has been interpreted by more than one senior source as "promoting him out of the way".

But Mr Lieberman was enraged by the leak, especially as it first appeared in Yisrael Ha-Yom, the daily owned by American billionaire, Sheldon Adelson, and widely regarded as Mr Netanyahu's mouthpiece.

He told a meeting of his Yisrael Beitenu faction on Monday that he "read in shock that Netanyahu appointed Arad in London", emphasising that "I'll be considerate of his stance but all the appointments will be made by the Foreign Ministry only".

While it seems that Mr Lieberman is in favour of Mr Prosor moving to New York, he categorically ruled out Mr Arad's appointment saying that "there are enough people in the Foreign Ministry, including people born in London".

This led to speculation that the leading candidates were senior British-born diplomats including ambassador to India, Mark Sofer, Jeremy Issacharoff, deputy director general for strategic affairs in Jerusalem, and Daniel Taub, the highly regarded deputy legal adviser at the ministry.

But one senior official in Jerusalem warned any of the prospective candidates against preparing his credentials to the Court of St James prematurely.

"This is first and foremostly a political argument between Bibi and Lieberman. If they reach an agreement on the issues that really matter to Lieberman, he could suddenly become very flexible over the ambassador to Britain.

"And besides, Lieberman may find himself with an indictment on money-laundering in a matter of weeks and then Bibi will become the temporary foreign minister. Then he will not lose even a moment in appointing Arad."