The leader of Kent County Council says he has no objections to Mayor Boris Johnson looking at the idea of an island airport off the north Kent coast but insists opportunities to expand existing regional airports should come first.

Cllr Paul Carter sought to clarify confusion over reports that he had claimed the Mayor was poised to put on hold his idea until a wider review of regional airport capacity had been carried out.

Mr Carter said he still maintained his opposition to the idea of “Boris Island” off the Isle of Sheppey but did not object to the Mayor pushing ahead with a feasibility study.

Earlier this week, Mr Carter spoke to Kent business chiefs about the scheme but insists he did not claim the Mayor was poised to scrap the plan.

The confusion has overshadowed a joint announcement by Mr Johnson and regional leaders about airport capacity in the south east that is due today.

Mr Carter said: “We need to make sure we look at the expansion in existing capacity. But if the Mayor want to maintain the idea of looking at a feasibility study, that is fine by me. The two can run together.”

Other regional airports could hold the key to absorbing additional demand, which could in any case fall because of the economic climate, he said.

Mayor of London - scheme 'very much alive'

In a statement responding to the earlier report about Mr Carter’s comments, the Mayor’s office said the Thames Estuary airport scheme was “very much alive”.

Mr Johnson said: “I certainly am not scrapping the idea of looking into a Thames Estuary Airport and have recently appointed one of the world's leading engineers, Doug Oakervee, executive chair of Crossrail, to lead the feasibility study into the Thames Estuary Airport.

"I have a duty to ensure the economy of the capital is secure and grows which is crucial not just to Londoners but everyone in the UK. “

The Mayor’s statement added: “That is why I am so keen to know what the alternatives are to Heathrow expansion and whether the idea of a new airport in the Thames estuary is viable or not.If there is an overriding economic, environmental, political or practical reason why this airport cannot be built it will not be built, but until we have looked into all the issues properly my idea is very much alive.”