Israel's prime minister warned Sir Keir Starmer almost a year ago to stop being 'weak' and take 'action' to stop anti-Semitic attacks in the UK, a letter leaked to the Daily Mail reveals.

The incendiary private message from Benjamin Netanyahu tore into the Labour government for allowing a campaign of 'violence against Jews' by 'Left-wing radicals and pro-Hamas extremists' to be 'amplified on your watch'.

And Sir Keir was personally blamed for 'pouring fuel on this anti-Semitic fire' by recognising the state of Palestine in what Israel's premier branded an act of 'appeasement'.

The revelations come with the Labour leader reeling from a crisis after a series of attacks on Jewish targets in recent months, including the stabbing of two men in Golders Green, north-west London, last week.

The letter sent in August 2025 reads: 'For years, anti-Semitism has haunted British cities. Since your election, it has intensified.'

It takes Sir Keir to task over 'the alarming rise of anti-Semitism in Britain and the lack of decisive action by your government to confront it'.

Mr Netanyahu wrote: 'Following Hamas's attack on the people of Israel on October 7, 2023, pro-Hamas extremists and left-wing radicals began a campaign of intimidation, vandalism and violence against Jews across Europe. In Britain, that campaign has amplified on your watch.'

Mr Netanyahu cited a number of attacks on the Jewish community in the months before he sent the letter, including Jewish teenagers being threatened with knives at a Tube station and diners at a kosher restaurant being assaulted. He wrote: 'These are not isolated incidents. They are a pattern. They are an epidemic.'

The letter was penned as the UK government announced it was going to recognise Palestine, bypassing decades of bilateral negotiations with Israel.

'Your call for a Palestinian state pours fuel on this anti-Semitic fire. It is not diplomacy, it is appeasement,' it read.

'It emboldens those who menace British Jews and encourages the Jew-hatred now stalking your streets.'

The Israeli prime minister urged Britain to follow the approach of the US, which he said had taken robust action to clamp down on anti-Semitism by deporting Hamas sympathisers and revoking the visas of foreign students inciting violence.

The US President was protecting the civil rights of American Jews by enforcing the law, protecting public order and prosecuting anti-Semitic crimes, it said.

He signed off writing that 'anti-Semitism is a cancer. It spreads when leaders stay silent. It retreats when leaders act. I call upon you to replace weakness with action and appeasement with resolve'.

Mr Netanyahu set a deadline for action by September 23, 2025, the Jewish New Year, warning 'history will not forgive hesitation'.

A No 10 spokesman said: 'The PM has been clear about his commitment to tackling vile anti-Semitism in the UK.'

The warning came months before what officials have described as the most serious surge in anti-Semitic attacks on British Jews in recent years.

Two worshippers were killed and several injured in a terror attack at Heaton Park synagogue in Manchester in October 2025

The UK's threat level was lifted from 'substantial' to 'severe' last Thursday for the first time in more than four years, following the stabbing of two Jewish men in Golders Green on Wednesday.

It followed a series of attacks in March when ambulances operated by a Jewish volunteer emergency service were set on fire, alongside further reports of attempted arson and attacks on synagogues in north London.