The Israeli-born treasurer of the Conservative Party has been left “surprised but delighted” after receiving a knighthood from former Prime Minister Theresa May in her resignation honours list.

Ehud Sheleg, who is director of the Halcyon Gallery in Mayfair, has donated at least £3 million to the Tory Party, but had not expected to be among the names announced in Tuesday’s announcement.

Mr Sheleg, known to friends as Udi, had been appointed last September as party co-treasurer alongside former chief executive Sir Mick Davis — but has worked as the main party treasure under new PM Boris Johnson following Sir Mick’s resignation in July.

His friendship with Mr Johnson stretches back to Mr Johnson’s days as London Mayor, with the Halcyon Gallery in New Bond Street once hosting a charity event for the Mayor’s Fund for London.

Mr Sheleg had been heavily involved in Tory fundraising efforts for several months before his official appointment to the role and is said to have “incredible respect” for Theresa May.

He has previously said he was “honoured” to take on the role of treasurer for what he said was the “sane part of the political spectrum” but admitted it would open him up for investigation into his business affairs.

It is understood that the Tel-Aviv born entrepreneur and philanthropist did not expect to receive any such honour at this stage of his life. But he was delighted to see his name on the most recent list.

He had a good professional relationship with the former PM, although his friendship with Mr Johnson, while said to be arms-length, is a more long-term one.

Conservative Party’s finances are also understood to have improved in recent months with wealthy individuals who were upset Brexit had not been delivered coming forward to donate money to the party, along with others convinced the threat of Jeremy Corbyn has to be combated.

Last year, Mr Sheleg told the Daily Telegraph: “Whether it’s the antisemitism issue, or the stance on the economy, or the overall approach to the world order, what is represented by Mr Corbyn and his close allies and the whole movement that is taking over the Labour Party, I think this is bad for Britain, bad for the whole world.

“What I have to go by is who is leading the Conservatives now, namely Theresa May and the people around her — they’re fighting the middle road. If one can, one should support the most sane of the options.”

He moved to the UK, with his first wife, who was English, and their children having already made an impact in the business arena through the art and technology sectors. In 2014 he married for a second time.

Discussing his upbringing he has said: “I was brought up, albeit in Israel, with the sentiment of very strong ties to Britain. In the family of nations, this has to be my favourite one. Second to my homeland, of course.”

Mr Sheleg’s father was in the RAF during the war and raised his son with a deep love of all things British.

In 1999, Mr Sheleg merged his own art management business with Halcyon, ran in Birmingham by Paul Green, who is also Jewish, and selling contemporary art.