The man who co-wrote a book with Donald Trump about the would-be president's business acumen says he has already made plans to live in Europe if he wins the election.

Journalist Tony Schwartz is credited alongside Mr Trump on the cover of The Art Of The Deal, which many commentators say it was instrumental in helping propel the businessman from being famous in New York to being famous across America.

Now Mr Schwarz says he does not want to live in a country where Mr Trump is president and fears that in office he would pursue his enemies "with a literal vengeance".