City of London head takes aim at Mayor Johnson

London Mayor Boris Johnson's leading role in campaigning for Britain to leave the EU is sending "unwelcome and unhelpful" signals to investors about the capital's future, the head of the City of London Corporation said on Tuesday.

The Corporation, which runs the only global financial centre to rival New York, last month came out in favour of Britain staying in the European Union when the country votes in a June 23 referendum.

In contrast, Johnson, who is responsible for running the whole of London, aims to convince voters into leaving the EU.

"The City of London is the leading international financial centre in the world," he told Reuters. "It is the most cosmopolitan major business city in the world and ... a step backwards from an international position, which I think many would see this as, is unwelcome and unhelpful."

Evans said the City of London wanted "informed debate".

"We want people to be out there with views, but I think people do appreciate Britain's international position and they like to see leading spokesmen in London being pro-Europe," he said at his historic Mansion House office, close to the Bank of England.

Johnson's support for leaving the EU has been viewed as a gamble aimed at securing the coveted top job of prime minister if Britain leaves.

London dominates the $5.3-trillion-a-day global foreign exchange market and is by far the most important financial centre in the EU. If Britons vote to leave, London faces losing the trade in trillions of euros in derivatives.

Evans, who is the 688th lord mayor which is an ambassadorial role for the small financial area known as the City of London, said Britain's EU membership had been "a great factor for inward investment" into the country.

"Britain's position as a major trading centre would, in my view, be harmfully impacted by a decision to leave," he said.