Twickenham top brass on Friday welcomed International Rugby Board clarification on the bidding to stage World Cup 2007.

Rival candidates England and France have both been instructed to re-submit their bids by January next year, with a final decision due three months later.

The IRB said one bid from each country should comply fully with tender document terms, while they are also allowing England and France to present a second option, proposing alternative structures.

England's 'preferred option' is for a 16-team World Cup, as opposed to the current 20-country format, plus an inaugural 32-team World Nations Cup for developing sides.

"In their respective bids to host RWC 2007, England submitted three options, one of which complied with the terms contained in the tender document, and two of which were radically different," said an IRB spokesman.

"The French bid, while it complied in all other respects, was in breach of the terms because the proposed dates of the tournament fell two weeks outside the prescribed time-frame.

"As a result the Board, in its wish to encourage innovation and in the interests of fairness, has instructed both unions to re-submit their bids, one which should fully comply with the tender document terms and one which can propose alternative structures."

Graeme Cattermole, chairman of the Rugby Football Union management board, said: "On behalf of the RFU, I am delighted that the IRB has clarified its statement from last night by providing further information.

"In particular, the IRB acknowledgement that our 'traditional' bid is a valid one and fully meets the requirements of the tender document.

"I am pleased that within their statement, the IRB welcomes 'innovation' and this provides us with a great deal of encouragement in pursuit of our 'preferred option' to host a 16-team Rugby World Cup and a 32-team Rugby World Nations Cup.

"We have already done a considerable amount of work on our 'preferred option' and following our international lobbying, we have received some very constructive feedback which will be incorporated into our plans," he added.

"The RFU is committed to supporting and assisting the IRB meet its objectives of increasing awareness, development and participation in the sport, as well as maximise revenues for distribution to the non-foundation unions.

"We will spend the next few months working towards persuading people that our bid is the right way forward in meeting these objectives."