He earned the nickname "America's mayor" for his response to the 2001 attacks on the twin towers.

Now, Rudy Giuliani is aiding Donald Trump's legal team as it fights to regain control over the controversy surrounding a payment used to buy the silence of porn star Stormy Daniels.

The former New York official, who was previously reported as a favourite to serve as secretary of state, took on the role in April after the exit of Mr Trump's attorney John Dowd.

Just two weeks into the job Mr Giuliani has sparked a political explosion after appearing to veer off script in his first TV appearance in the job.

In an interview with Sean Hannity on Fox News on Wednesday night, he said Mr Trump repaid personal attorney Michael Cohen the $130,000 given to Daniels to stay quiet about her alleged affair with the US President.

The payment has raised legal questions, including whether it could be considered an illegal campaign contribution.