Sean 'Diddy' Combs has revealed he thought he would be 'better off dead' as he expressed deep regret about his criminal past in a letter to the judge presiding over his case.

The fallen music mogul whined about the 'inhumane' conditions in prison in a four page letter to Judge Arun Subramanian ahead of his sentencing hearing on Friday.

Diddy hopes to be released almost immediately, whereas prosecutors have urged the judge to impose an 11-year sentence after the rapper was convicted of transportation to engage in prostitution. He was found innocent of more serious racketeering and sex trafficking charges during his blockbuster criminal trial in July.

'I have to admit, my downfall was rooted in my selfishness... Over the past year there have been so many times that I wanted to give up,' Diddy wrote in his heartfelt letter.

'There have been some days I thought I would be better off dead.