He pledged at a service on Wednesday night to mark the Jewish state's 60th birthday that Britain would continue to be "a true and constant friend of Israel in good times and in bad".

And he announced that he would soon by paying Israel a visit.

The prime minister told the Jewish community's Yom Ha'atzmaut service at London's Finchley Synagogue: "We will never reduce our efforts to secure for Israel a future free from terror, a future where - alongside a viable Palestinian state - children and the children of all your neighbours can believe in a brighter future."

Mr Brown praised his close friend the Chief Rabbi, Sir Jonathan Sacks, and recalled his own involvement in learning about Israel when he was a child.

The premier noted that he was well aware of Israel's achievements and also its vulnerability.

With his father - a church minister - being a frequent visitor to Israel, he said he learned of the fight for a Jewish homeland, the Balfour declaration and the promises made - some of which have been honoured and some which have been broken. "I learned of the ancient dream of the Jewish nation becoming reality in the modern state of Israel," Mr Brown went on.

"And I was taught, too, of the sufferings and the struggles and the Holocaust - the greatest crime that was ever committed against humanity." He announced that against the backdrop of the current political process - which presented all with the real opportunity to move forward - he would be visiting Israel in July at the invitation of Ehud Olmert.

Noting that the previous day had been a day of memorial, he was well aware of just how many victims and persecution were part of Israel's history.

He was also aware of the determination of the Jewish people to ensure that discrimination in all its forms must be fought.

"It is that conviction - and my knowledge that it is the conviction of the people of Israel - why I have been, and remain, a lifelong friend and supporter of Israel".

He went on to praise the British Jewish community not only for its long and distinguished history in helping build the UK but also in helping create the State of Israel. He also praised them for their role in developing, enhancing, defending and helping Israel ensure its peace and security over the last 60 years.

Noting the Chief Rabbi's contribution, he added that Israel was not just a state.

It had become - and remained - a pluralistic society "where politics were hard fought and democracy never abandoned". Mr Brown said: "It is a country that has become - even facing difficulty and struggle - a world leader in science and innovation.

"It is becoming a thriving global economy."

The attributes were a tribute to those who founded and led the state and "a good reason to celebrate today."

Mr Brown said: "Let us celebrate a nation that can triumph over attempts at isolation, threats of war and threats of terrorism and emerge even stronger, tending to its young, caring for its sick, cherishing its old.

"Let us help Israel find a truly secure place in a peaceful Middle East."