Formula One carmakers, threatening their own series, announced on Monday that their teams had submitted entry forms to continue in the FIA world championship in 2008.

"The five teams united through the Grand Prix Manufacturers Association...have submitted their entry forms for the 2008 FIA Formula One world championship," the GPMA said in a statement.

The teams are champions Renault, BMW [Images] Sauber, McLaren Mercedes, Honda and Toyota.

However a spokesman for the carmakers' group said the announcement did not mean a deal had been done with Formula One's commercial supremo Bernie Ecclestone to end all talk of a 'rival series'.

"There are several open issues still to be discussed and it is too early to speak of a final agreement," he said.

Formula One's governing body told the teams last week that they had to sign up for 2008, when an existing commercial agreement expires, by the end of March or be frozen out of the decision-making process.

By submitting their entries, the teams have calmed sponsors and ensured that the carmakers will have a say in discussion of proposed regulations such as a controversial freeze on engine development.

At the same time, the carmakers can continue their negotiations with Ecclestone without having to do a deal before March 31.

STILL UNITED "The teams look forward to the FIA's acceptances, and to beginning discussions with the FIA in order to finalise the regulations for 2008," the GPMA statement added.

"The GPMA members are united and remain committed to improve the sport for the benefit of all stakeholders.

"Significant progress has been made in the negotiations between the GPMA and the commercial rights holder, and discussions are ongoing."

The GPMA have threatened to set up their own series from 2008 unless they get a far greater share of the revenues, greater transparency in the way the sport it is run and guarantees of equal treatment for all.

However they have said a deal is close and the threat of their own series has increasingly been seen as a mere bargaining chip. Monday's announcement will only add to that feeling. Six other teams, including Ferrari [Images] and Williams, powered by Cosworth this year, have already committed to the FIA championship beyond 2007 and there remains a possibility of new teams also seeking to join.

The FIA added to the rules controversy on Monday with a separate statement announcing that they had agreed with Renault, Ferrari and independent engine maker Cosworth on proposals for a five-year engine freeze from 2008.

The governing body said those present would also seek to change the 2007 sporting regulations to bring forward the 2008 proposals.

The engine regulations changed this season, with teams using 2.4 litre V8 units instead of 3.0 litre V10s. So far, champions Renault have shown the greatest reliability in winning the first two races.

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