Godfrey Bloom, the senior Ukip politician under fire for referring to "bongo bongo land", has come up with another reason why the phrase is not racist – it refers to a white antelope.

The MEP said the expression was "not racist at all" because the dictionary defined the "bongo" as a white forest-dwelling animal.

Bloom had previously issued a qualified apology to anyone "genuinely offended" by the phrase, following pressure from his party leader, Nigel Farage. However, on Thursday morning he was back on the airwaves defending the expression once again.

"If anybody would care to take the trouble to get out the Oxford dictionary this morning and look it up, you'll find that bongo is a white antelope, lives in the forest, there is no connotation of racism about it whatsoever," he said. "Bongo land is the land of the antelope.

"Some people have interpreted it as a racist remark but there is no evidence in any dictionary at all that it implies racism."

Bloom this week found himself at the centre of a furore after he was recorded calling for an end to foreign aid going to "bongo bongo land", sparking accusations the phrase had racist connotations.

MPs and campaigners have pointed out that Alan Clark, the former Tory minister, was first at the centre of a "race row" 30 years ago for using the phrase during a Foreign Office meeting to refer to African countries. Dictionaries define the word "bongo" as either a small drum beaten with the fingers or a red-brown antelope found in Africa.

As the controversy continued into its second day, David Cameron waded into the row, describing the comments as "offensive" and representative of a "sort of 'stop the world, I want to get off' approach" to politics.

Bloom has admitted he did not know what he meant by the phrase, but that "maybe" it could have been said in relation to African countries.

He also suggested the phrase could have been "misconstrued by President Bongo of the Gambon", apparently referring to President Ali Bongo of Gabon.

Speaking to Channel 4 News on Wednesday, the MEP said he had simply meant to describe "corrupt despots across the globe … who either spend the money we give them on arms or who misdirect it".

Asked whether Farage thought the phrase was racist, Bloom said: "I think he does and it's a generation thing … If he tells me so it must be so."

He later walked out of the Channel 4 interview in frustration at the questioning.

The row is another example of the challenge facing Farage as he forges Ukip's reputation for straight-talking politics at the same time as pledging to wipe out any intolerance among its ranks.

In an interview with Public Service Europe this week, he said: "It is a very difficult balance because on the one hand we are a non-politically-correct party that believes in free speech and debate, and we welcome strong-minded individuals that aren't just cardboard cut-out human beings. But on the other hand, we can't allow the basic Ukip message to be taken by extremism or by lunatics bringing it into disrepute. It's a difficult line to tread."

Bloom's original comments, first reported by the Guardian, were made to a meeting of supporters in the West Midlands last month.

In the recording he said: "How we can possibly be giving a billion pounds a month when we're in this sort of debt to bongo bongo land is completely beyond me.

"To buy Ray-Ban sunglasses, apartments in Paris, Ferraris and all the rest of it that goes with most of the foreign aid. F-18s for Pakistan. We need a new squadron of F-18s. Who's got the squadrons? Pakistan, where we send the money."

The party's leadership asked Bloom not to use the phrase again after MPs and anti-racism campaigners called for him to be excluded from their list of candidates for the European elections, which are due to be announced this week.

Rushanara Ali, a shadow development minister, said the party should take action against Bloom if Farage was "serious about getting rid of racism and intolerance" in his party.

Steve Crowther, the Ukip chairman, later said: "We are asking Godfrey not to use this phrase again, as it might be considered disparaging by members from other countries. However, foreign aid is an extremely important debate that needs wider discussion."

Two months ago Farage ensured an Italian MEP was expelled from Ukip's European alliance for saying a black minister in Italy was part of a "government of bongo bongo" who would want to impose "tribal traditions", and would be better suited as a housekeeper.