Richard Coughlan plans to subject an audience to more than nine hours of his improvised, rhyming patter – and admits ‘I have no experience in freestyle rapping at all.’

The current record is 8 hours and 45 minutes, set by experienced Toronto rapper D.O. in 2003

Coughlan, said: ‘This gig will be my first ever rap show. I have been prasticing in various ways at home and in other social situations but other than that I am a total newbie. I guess that's why it's funny.’

He will be making his attempt during the Edinburgh Fringe, basing his rap on written suggestions from the audience and witnessed by an official adjudicator

Guinness rules allow a 15-minute break every four hours, and he can pause – but not for more than thirty seconds.

Coughlan added: ‘I have to improvise and create everything I say off the top of my head. The main problem in maintaining the rap itself will be simply keeping my brain from dissolving, this is why the 30-second pause rule is useful as it means you can pace yourself at the start and take it easy.’

The gig will take place at Lindsay’s in Edinburgh as part of the Laughing Horse Free Festival and will raise money for the kidney charity the James Whale Fund.