Gordon Brown will today use the first ever speech by a British prime minister to the Israeli parliament to issue a clear threat of tougher international action if Iran fails to halt steps towards becoming a nuclear military power.
"Iran now has a clear choice to make: suspend its nuclear programme and accept our offer of negotiations or face growing isolation and the collective response not of one nation, but of many nations," Mr Brown will say from the Knesset floor.
The threat will be coupled with a strongly personal restatement of his affection for Israel, inherited from his father, a Church of Scotland minister who had learnt Hebrew.
Mr Brown yesterday visited the Yad Vashem memorial museum commemorating the six million Jews killed in the Holocaust, and today will stress his lifelong affinity with Israel and declare that it is "totally abhorrent for the President of Iran to call for Israel to be wiped from the map of the world." Mr Brown's father John, chairman of the Church of Scotland's Israel Committee, would show his family films on an old projector after his at least twice-yearly trips to the Holy Land. "I will never forget those early images of your home in my home and the stories my father would tell. I followed the fortunes of an age old people in their new country."
Saying there was "never a time as I was growing up when ... I was not surrounded by stories of the struggles, tribulation and triumphs as the Israeli people built their new state," he will add: "To those who question Israel's very right to exist we say: the people of Israel have a right to live here, to live freely and to live in security."
At the same time Mr Brown may also use his Knesset speech – as the French President Nicolas Sarkozy did last month – to couple warm praise for the 60-year-old Israeli state with an exhortation to it to make the concessions needed to end the Middle East conflict, including making East Jerusalem the capital of a future Palestinian state.
After meeting the Palestinian President Mahmoud Abbas in Bethlehem, the Prime Minister called for an end to the settlement expansion which the moderate Palestinian leadership in the West Bank says is hampering efforts to agree the outlines of a two state solution. Mr Brown had earlier passed the through the main checkpoint into the West Bank city where he saw the nine-metre high concrete wall – part of the Israeli military's 450-mile separation barrier – dividing the city from Jerusalem and the Jewish settlements in Palestinian territory south of Jerusalem.
While stressing Israel's right to live in security, he declared: "As a child, I learnt about Bethlehem from the Bible as a symbol of peace and a symbol of hope. But today, the wall here is graphic evidence of the urgent need for justice for the Palestinian people and an end to the occupation and the need for a viable Palestinian state."
Mr Brown, who was accompanied by a delegation of senior British businessman, as he promoted investment in the Palestinian economy, yesterday announced a further £60m of UK government money for the Palestinian Authority on top of the £500m he has already pledged over three years.
Avner Shalev, the director of Yad Vashem, said that Mr Brown had been "very moved" by his visit to Yad Vashem, where at the end of his tour he wore a kippa as he rekindled the eternal flame in the Hall of Remembrance. At the Janos Korczak memorial to the 1.5 million children who died in the Holocaust, he wrote in the visitors' book: "Nothing prepares one for the story that is told here – of the atrocities that should never have happened and the truth that everyone who loves humanity should know."
