Lawyers are to write to Barack Obama and the ambassadors of every country in which Top Gear airs asking them if the BBC motoring series should continue to be broadcast, following Jeremy Clarkson's mumbled use of the N-word.

Lawrence Davies, director of law firm Equal Justice, branded Top Gear as "racist" and told MediaGuardian his firm did not accept the apology Clarkson has made.

He also asked who had approved the scene when Clarkson is shown choosing between two cars by reciting the words to the nursery rhyme "eeny, meeny, miny, moe" and apparently mumbling the N-word.

Davies said: "We are to write to every ambassador and the US president next week asking them to consider the evidence and then to decide if this racist show should be broadcast in their country in future."

Top Gear is broadcast in around 214 territories around the world.

Davies also asked whether or not the scene was scripted and the use of the mumbling approved in advance.

However, MediaGuardian understands that the rhyme "eeny, meeny, miny, moe" was not scripted.

Equal Justice represented Indian-born actress Somi Guha when she complained to the BBC about Top Gear earlier this year over Clarkson using the word "slope" as a Thai man crossed a bridge in an episode set in Burma.

Top Gear producer Andy Wilman said at the time: "When we used the word "slope" in the recent Top Gear Burma special it was a light-hearted wordplay joke referencing both the build quality of the bridge and the local Asian man who was crossing it.

"We were not aware at the time, and it has subsequently been brought to our attention, that the word 'slope' is considered by some to be offensive and although it might not be widely recognised in the UK, we appreciate that it can be considered offensive to some here and overseas, for example in Australia and the USA.

He added: "If we had known that at the time we would not have broadcast the word in this context and regret any offence caused."

Davies' firm also represented Iris de la Torre, who complained about an episode of Top Gear in 2011 which compared cars to Mexican stereotypes and for which the BBC subsequently apologised. That episode was made just before the controversial "eeny, meeny, miny, mo" footage, which was not broadcast at the time but was leaked to the Daily Mirror earlier this week.

Davies said: "Clarkson claimed he 'did everything in my power to make sure that that version did not appear in the programme that was transmitted' … The obvious thing that any non-racist would have done is to not use the rhyme at all or failing that to simply substitute another word such as 'tiger' in the take. There was never any need to mumble the N-word repeatedly."

He also attacked education secretary Michael Gove for defending Clarkson on ITV's Good Morning Britain.

"Michael Gove, a close ally of Clarkson's friend, the PM, rallied to Clarkson's defence today. We worked with him on the Baby P whistleblower case so we know him well. That the person responsible for our children's education should condone an apologetic racist before the actual investigation has begun (let alone concluded) is an absolute disgrace," he said.

"The BBC has lost all credibility. Even Ukip would have sacked Clarkson and his team for their gross misconduct. The BBC will not because they are making money out of the show."

The BBC is still deciding what action to take and has yet to confirm if Clarkson will take part in the next series of Top Gear, which is due to begin filming soon.

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