A key figure in South Africa’s football World Cup bid has broken ranks with the government to suggest there might be some truth to a claim that a $10m bribe was paid to secure the 2010 tournament.

Tokyo Sexwale told the BBC the US allegations were “worrisome”.

The government says it paid $10m to accounts controlled by then Fifa vice-president Jack Warner to support football development in the Caribbean.

An official said the money, transferred by Fifa, was given without conditions.

But Mr Sexwale – a former Robben Island prisoner, government minister, and a member of both the World Cup bid team and local organising committee – has now openly questioned the credibility of the claim that the money was a “donation”.

“Where are the documents, where are the invoices, where are the budgets, where are the projects on the ground?” asked Mr Sexwale.

“If they are not there, you are going to leave the FBI [US Federal Bureau of Investigation] interpretation intact,” he said.