In trenchant comments to the Balfour 100 celebration dinner, Prime Minister Theresa May set out a red line over the Balfour Declaration: “When some people suggest we should apologise for this letter, I say absolutely not”.

Britain, she said, was “proud of our pioneering role in the creation of the state of Israel. We are proud to stand here today together with Prime Minister Netanyahu and declare our support for Israel. And we are proud of the relationship we have built with Israel”.

Mrs May said that Britain looked forward to developing that relationship. She and Mr Netanyahu had spent time in Downing Street on Thursday discussing “deepening our links in areas where Israel is leading the world – in areas like agriculture, health, science, technology and innovation. Israel is the true start-up nation and we are proud to be your partner”.

The Prime Minister said Britain remained “absolutely committed to Israel’s security”, and that it would “always support Israel’s right to defend itself”.

She praised Israel “as a symbol of openness, as a thriving democracy; and a beacon to the world in upholding the rights of women and members of the LGBT community”.

Chaim Weizmann at the signing of the Declaration of Independence

Chaim Weizmann at the signing of the Declaration of Independence

But the Prime Minister acknowledged that there was still “unfinished business” with Balfour, because “his fundamental vision of peaceful co-existence has not yet been fulfilled”.

She said that it was vital for everyone to work towards a lasting peace for both Israelis and Palestinians, and welcomed the presence at the dinner of the US Secretary of Commerce, Wilbur Ross, to whom she gave a message of assurance about British support for peace efforts by the Trump administration.

Mrs May reiterated her belief that any peace deal must be based on a two state solution “with a safe and secure  Israel alongside a viable and sovereign Palestinian state. Let us be honest with each other: there will need to be compromises from each side if we are to have a realistic chance of achieving this goal – including an end to the building of new settlements and an end to Palestinian incitement too”.

But she said that in her view, Balfour’s vision of peaceful coexistence did not include boycotts of Israel — “they are unacceptable and this government will have no truck with those who subscribe to them”. And the Prime Minister also recognised “that there is today a new and pernicious form of anti-Semitism which uses criticism of the actions of the Israeli government as a despicable justification for questioning the very right of Israel to exist.This is abhorrent and we will not stand for it”.

Britain would never forget where that kind of hatred could lead, Mrs May declared, which was why it was “right” that there was going to be a National Holocaust Memorial next to Parliament.

She concluded: “Let us take inspiration from the vision Balfour showed as we work together for that future where Arabs and Jews can live in peaceful co-existence. And as we look to that future, let us mark with pride what has been achieved with the creation of the state of Israel and – in Balfour’s own words – “a national home for the Jewish people.”