Britain has appointed its first Jewish ambassador to Israel. And Matthew Gould, a high-flying Foreign Office diplomat, is optimistic that his posting — to begin in autumn 2010 — will send out a significant message, both to his hosts and the UK Jewish community.

Mr Gould, 38, is currently Principal Private Secretary to Foreign Secretary David Miliband. Two of his predecessors as PPS to the foreign secretary of the day, Simon McDonald and Sherard Cowper-Coles, also went on to become British ambassador to Israel, so there is an established precedent.

Curly-haired, slight of build and warm of demeanour, Matthew Gould is the youngest of three brothers, brought up in Wembley, north London. “First we went to Harrow and Wembley Liberal shul,” he volunteers, “then to Middlesex New Synagogue.”

It is a surreal conversation to be having in a Foreign Office corridor as cleaners vacuum around us. For despite being tipped for a starry future and being at pains to point out that he hopes he got the Tel Aviv job because he was the best person for the post, being Jewish is clearly important to him.

“When I joined the Foreign Office” — in 1993, after taking a philosophy and divinity degree at Cambridge — “friends and family queued up to say that it was a nest of antisemitism. But in 16 years I have never experienced a single antisemitic moment or a sign of it. ”

He is firm in his belief that the Foreign Office has changed; and he himself has been an architect of that change. Mr Gould was among a group of self-described Young Turks who helped to write the Foresight Report, a series of recommendations for improvement of the foreign service.

“I’d like to think I went some way towards shifting some Foreign Office attitudes. It has changed quite a lot. It was much more formal and hierarchical than it is now.”

He spent three years as Second Secretary at Britain’s embassy in Manila, finding time to campaign against child sex abuse in the Philippines, and then a further three years as speechwriter to the late Robin Cook, Foreign Secretary in Tony Blair’s first cabinet.

Mr Cook was famously declared persona non grata in Israel after he laid a wreath at Deir Yassin, rather than go to Yad Vashem, a move compounded by a furious verbal attack he made on settlers at Har Homa.

“I know about the depth of feelings on that issue,” says Mr Gould, mildly, although he did not accompany Mr Cook on that trip.

More pertinent, perhaps, was his input when Mr Cook hosted and convened the first London Nazi gold conference in 1997. Mr Gould was awarded an MBE during that period, aged just 26.

Since then he has served in two Islamic postings, Islamabad and Tehran — he was deputy head of mission in Iran.

“I made a point of going to shul in Tehran,” he says. It was both a means of expressing support to Jews there and putting down a marker to the Iranian government that there was a watching brief on how it treated its minorities.

After two years as foreign and security policy counsellor in Washington, he was brought back for a brief stint as private secretary for foreign affairs to the departing Prime Minister, Tony Blair, before taking up his present job in July 2007 with David Miliband.

How did he see the Israel job? It is not exactly a conventional “big job” for an ambitious diplomat — although it could be argued that it is a measure of how seriously Whitehall takes the situation that it will send someone like Matthew Gould to Tel Aviv.

Although he gives a standard reply: “I can’t think of a job I would rather have,” there is a sense that he has a genuine commitment to it. “There is no doubt of the political and geopolitical importance of Israel and of its neighbours. Any foreign secretary or prime minister will spend a good deal of time on the Middle East. Tt has always been at the heart of foreign policy. Israel has a fantastic, open and argumentative culture, which is both challenging and extremely rewarding for an ambassador.”

He spent time backpacking around Israel after university, and was frequently taken by his grandparents to Eilat and on tours around Israel. He has second cousins there, too. Being the first British Jewish ambassador to Israel is “a question I have given a lot of thought to. I don’t think it’s straightforward. I thought hard about it before applying. It will give me, I hope, an insight to the history of the Jewish people, prior to Israel’s creation — because in a sense that is the story of my own family.

“It means that I come with an understanding and a passion for pursuing the policy the British government wants me to pursue. I will be there as the British ambassador, but I will still be absolutely passionate as to what I see as the three key points which underlie Britain’s policy towards Israel: its legitimacy and right to exist; its long term security, based on peace; and the strongest, widest, and best possible relationship between Britain and Israel.”

He adds: “About being Jewish and doing the job: there will be a certain amount of expectation, of scrutiny, that will come with it. What the British ambassador in Tel Aviv says is closely scrutinised, anyway. I hope, by making clear that I’m not there as the Jewish ambassador, I’m the British ambassador, people will understand.”

He has to leave: he has a Hebrew lesson. His wife, Celia, is also studying the language; the couple, not long married, hope to start their family in Israel. “She is as excited as I am about going.”

I ask what he thinks about his Foreign Office colleague, Rowan Laxton, who was convicted of racial abuse after an antisemitic outburst in a London gym earlier this year.

After suspension and an internal disciplinary process, Laxton has resumed his employment with the Foreign Office. “I think it would be a great shame if people drew the conclusion [from that incident] that the Foreign Office was inherently Arabist. There lingers in part of the community a stereotype of the Foreign Office: that is a reality long out of date, and I hope my appointment goes some way to changing that.”