LONDON (Reuters) - A 'No' vote in Italy's forthcoming referendum on constitutional reform would be negative for the country's economy and its creditworthiness, ratings agency Fitch said on Tuesday.

"If there was a 'No' vote, we would see that as a negative shock for the Italy economy and for Italian creditworthiness," said Edward Parker, managing director at Fitch during a briefing in London.

Prime Minister Matteo Renzi has staked his political future on the ballot which is due to be held between November 15 and December 5. Recent polls have put the 'No' camp marginally ahead.

(Reporting by Marc Jones, writing by Karin Strohecker, editing by Nigel Stephenson)