Boris Johnson is debasing the EU referendum debate with "ludicrous" arguments, journalist Paul Mason has said.
Mr Mason, a former Channel 4 News and BBC Newsnight editor, said Mr Johnson's approach "shows what a £35,000 a year education at Eton buys you".
He made the comments appearing on the BBC's Question Time programme.
Mr Johnson has commited himself to campaigning to leave the European Union and taken centre stage in the campaign.
He has caused controversy on a number of occasions, however: by suggesting that "part-Kenyan" Barack Obama had an "ancestral dislike" of Britain, and by claiming the EU's aims were similar to those of Adolf Hitler.
The Mayor of London also attracted criticism for inaccurate claims about EU regulations on the sale of bananas.
