It would be recalled that speaking with the Queen, the archbishop of Canterbury, Speaker John Bercow and Commons Leader Chris Grayling, on the anti-corruption summit in London, Thursday, Cameron described Nigeria as one of the most corrupt countries in the world.
It was not clear whether he knew the comments were being recorded.
“We’ve got some leaders of some fantastically corrupt countries coming to Britain… Nigeria and Afghanistan, possibly the two most corrupt countries in the world,” Cameron said.
Archbishop of Canterbury Justin Welby intervened to say: “But this particular president is not corrupt… he’s trying very hard,” before Speaker John Bercow said: “They are coming at their own expense, one assumes?”
The government will host world and business leaders at the summit on Thursday in London, aiming to “galvanise a global response to tackle corruption”.
During a pre-summit event in London, Buhari was asked to respond to Cameron’s comment that Nigeria and Afghanistan were “possibly two of the most corrupt countries in the world”.
He has since noted that the leaders of both countries are working hard to combat corruption.
“I am not going to demand any apology from anybody. What I am demanding is the return of assets,” Buhari said at an event, to applause from Nigerians in the audience.
“What would I do with an apology? I need something tangible,” he said, rubbing his fingers together in a gesture commonly used to refer to money. The audience laughed.
Buhari did not, however, specify which assets he was talking about.
British police have conducted several investigations in recent years into assets held in Britain by Nigerian politicians, including two former state governors and a former oil minister. One of the ex-governors is serving a prison sentence in Britain after pleading guilty to money-laundering.
Nigeria is listed at number 136 out of 167 in campaign group Transparency International’s latest Corruption Perceptions Index, an annual ranking of countries in which a higher number indicates a higher level of perceived corruption.
Earlier, Commonwealth Secretary General Baroness Scotland said Mr Cameron’s remarks had been ‘unfortunate’ and countries like Nigeria needed support rather than criticism.
Mr Cameron’s candid comments risked causing diplomatic ructions ahead of the major international anti-corruption summit in London on Thursday.
As well as Buhari, and Afghan President Ashraf Ghani is due to attend. He has also acknowledged corruption in his country and pledged to clean it up.
The gathering of the world’s political and business leaders in London will aim to ‘galvanise a global response to tackle corruption’ and is being staged in the wake of the Panama Papers leak, which revealed widespread tax avoidance among the world’s elite earlier this year.
Afghanistan is at number 166 in campaign group Transparency International’s latest Corruption Perceptions Index – second from bottom.
Only North Korea and Somalia, jointly ranked at number 167, are perceived to be more corrupt.
The Presidency, Tuesday, expressed ‘shock’ at the unguarded comment, saying that Cameron must have been looking at an old snapshot of Nigeria.