Sir Keir Starmer announced his plan to recognise a state of Palestine after an emergency Cabinet meeting on Gaza last week - Toby Melville/Reuters

Malcolm Shaw KC, a leading lawyer, said that the recognition plan “would create a troublesome precedent and could well challenge and ultimately destabilise an international system founded upon a common understanding of what it is to be a state”.

The fresh legal opinion, seen by The Telegraph, was circulated to the Prime Minister, Lord Hermer, the Attorney General, and dozens of influential Labour MPs.

It was commissioned by Lord Mendelsohn, the Labour peer, in response to Sir Keir’s decision to recognise a State of Palestine in September unless Israel meets certain conditions.

Lord Mendelsohn, a Labour peer, commissioned Malcolm Shaw KC to write a legal opinion on the Government’s plan - Shutterstock

The warning comes after Hamas made it clear it will not disarm unless an independent Palestinian state is established.

The militant group took the step of issuing a statement “in response to media reports quoting US envoy Steve Witkoff, claiming [Hamas] has shown willingness to disarm”.

It said: “We reaffirm that resistance and its arms are a legitimate national and legal right as long as the occupation continues.

“This right is recognised by international laws and norms, and it cannot be relinquished except through the full restoration of our national rights – first and foremost, the establishment of an independent, fully sovereign Palestinian state with Jerusalem as its capital.”

Hamas added that Mr Witkoff’s trip on Friday to a Gaza aid distribution site was “designed to mislead public opinion, polish the image of the occupation, and provide it with political cover for its starvation campaign and continued systematic killing of defenceless children and civilians in the Gaza Strip”.

Mr Shaw’s legal opinion says the Prime Minister’s plan to recognise the state of Palestine is “premature and may have unintended consequences” and that it “confuses and distorts” any attempt at a peaceful two-state solution.

‘A prize for precipitating war’

He describes Sir Keir’s decision to make statehood dependent on the behaviour of Israel, a “third country”, as “remarkable”.

“This is exceptional and, frankly, not in keeping with the tenor of the relevant international principles,” he wrote.

“Recognition at the current time will be seen as a prize for precipitating the war on Oct 7 2023 with its attendant rapes and massacres.”

Mr Shaw also argues that the Palestinian territories “do not currently satisfy” the criteria for a state.

Some 40 peers warned this week that recognising Palestine in the process set out by the Prime Minister would be illegal. They included Lord Pannick KC and Lady Deech, both respected lawyers and patrons of UK Lawyers for Israel, an association of British lawyers who are supportive of Israel.

But Mr Shaw’s opinion could pile further pressure on the Government to reconsider its legal position with regards to recognition.

He further argues that since both Israel and the Palestinian territories are still bound by the Oslo Accords, the agreement that remains the legal framework that governs the relationship between Israel and the Palestinians, proper recognition at this time is not possible.

Malcolm Shaw at the International Court of Justice, where he is representing Israel in its case against South Africa, which has accused it of genocide in Gaza - Thilo Schmuelgen/Reuters

Mr Shaw, who is the author of a standard legal textbook on international law, is currently representing Israel in its International Court of Justice (ICJ) case against South Africa, which argued that Israeli forces had committed genocidal acts in Gaza.

While Sir Keir has always agreed to the principle of recognising a Palestinian state at some point, he was reluctant to do so until his surprise announcement this week.

The Prime Minister appears to have been influenced by a number of factors, including the worsening starvation crisis in Gaza, pressure from international allies such as Emmanuel Macron, and increasingly vocal calls for immediate recognition from his own MPs.

The setting up of a rival Left-wing political party under Jeremy Corbyn, which calls for an independent Palestinian state, may have also put pressure on Sir Keir to act.

On Saturday, protesters from the activist group Youth Demand blocked roads in the Holland Park and King’s Cross areas of London as they called for an immediate British trade embargo on Israel.

On Thursday, Labour MPs supportive of Israel reportedly clashed with Jonathan Powell, Sir Keir’s national security adviser, in a meeting about the recognition announcement.

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