It gets my goat when people call UKIP racist

"I realised there was no hope for this country being ruled from Europe," he says. "The interference is unacceptable. I believe in trade, but not in being ruled by bureaucrats we haven't voted for."

Reid has now donated a floor of his law office building in Mayfair to be used as Ukip's London headquarters. But many might question why a descendent of Eastern European immigrants who came to Britain in the early 1900s, would back an anti-immigrant party that might have turned away his ancestors? "Let me clear this up," he says, shaking his head at the suggestion.

"We are the party of immigration. We actively encourage immigration. What we want is controlled immigration, a policy that allows the best and most skilled to come into this country." I raise my eyebrow.

"To give you an illustration," he continues. "If the best doctor who has the skills we require happens to be in Africa; and there is a doctor in Latvia who is not as well-qualified; under present legislation we have to give the job to the Latvian.

"We also have no problem with genuine asylum seekers - that's what this country is about and what it's made of.

"But," he pauses. "We have people coming here simply to take - we do not believe that sort of immigration can be sustained or afforded by the country."

Reid believes the country needs a revamp, starting with the removal of untrustworthy politicians: "We can bring about change and the Westminster bubble is no longer going to be allowed to rule us with a lack of common sense."

It's a bold statement coming from a member of the party that lately got into bed with Polish MEP Robert Iwaszkiewicz, whose party leader questions the Holocaust.

But he refutes any suggestion that Ukip appeals to racist sentiments. "If I thought that Ukip was racist or antisemitic, I wouldn't work with them," says the West London Synagogue member. "It has never been racist. We will expel anyone we find to have had that sort of background.

"We had a multi-cultural rally where our members who were Sikhs, Muslims and Jews turned up. Then, a load of Hope Not Hate [campaigners] - all white - were screaming 'racists' at them. It was quite unbelievable."

As our conversation continues, it becomes clear that there's a more personal reason for his decision to leave the Tory party.

He claims that a local Conservative council has put his pet project - the Belmont Children's Farm in Mill Hill - under threat.

"Barnet council spends its life trying to close the farm down, while their schools send me thank you letters for either having come here to visit or the work we've done with groups in the community," he says. "A lot of this small-mindedness motivated me to join Ukip."

It was here, among 180-acres of farmland, which also houses his 17th-century home, that we met.

Reid, dressed in a suit and tie paired with walking boots, stood by a racehorse-drawn carriage, that he - also a race-horse trainer - steered around the site he once dreamed of turning into "a centre of equestrian excellence".

After being inspired to open the farm by frequent visits to Golders Hill Park as a child, the father-of-one is now involved in the day-to-day running of the project - from lambing to feeding 30 species - over 1,000 animals - before he heads to his central London office. Even Nigel Farage and Mr Reid's former client, the late Lord McAlpine, have had impromptu tours around the farm.

"This farm is enjoyed by everyone; we get the most religious Jewish and Muslim people here. In fact, this is what Britain ought to be about," he says over the sound of a rooster.