In a video circulated through the world's media, Cameron could be seen speaking to the Queen, Archbishop of Canterbury Justin Welby and Speaker Justin Welby. They were at Buckingham Palace at an event to mark the Queen's 90th birthday.

RELATED: UK PM calls Nigeria and Afghanistan "fantastically corrupt"

They were speaking about an anti-corruption summit in London.

"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.

But, in an interview with the BBC, President Mahama said "finger pointing" should not be the solution to issues of corruption, but rather how to have the correct systems in place to curtail the menace.

"I think that it doesn’t make a good environment when there is a finger pointing amongst us, we must be working as partners."…so yes we must look at the sources of corruption, we must put the systems in place that prevent it from happening but when it has happened we must look at these advanced and developed countries where these monies are hidden and can be returned to their legitimate owners in the developing world," President Mahama added.

The two countries, Nigeria and Afghanistan are known to be plagued with corruption issues. In the 2015 Transparency International report, Nigeria was ranked at 136, and Afghanistan at 167 out of 168 countries.