At least four teams are keen to break into Formula One and just need affordable engines to do so, according to FIA president Max Mosley.

The head of the sport's governing body, outlining the state of play over proposed rule changes for 2005 and 2006, told an Italian Grand Prix news conference on Friday that engines remained the crucial issue.

He also made clear that he would not bend to pressure from dissenting carmakers.

"If all these rule changes go through, and it all works as it should do and we have a really good season in 2006, which I think we will have, then you will probably find one or two new teams will come in and the whole thing will start to regenerate," said Mosley.

"The unhealthy thing about Formula One at the moment is that we haven't had any new teams other than Toyota and we need the professional racing teams which always have been the backbone of Formula One.

"There are at least four that I know of outside who would like to come in but, contrary to popular belief, it's not the $48 million deposit that's stopping them, it's the availability of competitive engines.

"If we can get them competitive engines, they'll be in."

Toyota, who made their debut in 2002, were the last newcomers since Jordan in 1991. There are just 10 teams, with room for at least two more, but would-be entrants have to post a $48 million bond at present.

SERIOUS CONCERN

The FIA is determined to force engine manufacturers to switch from three litre V10s to 2.4 litre V8s from 2006 with engines also lasting for two races each from 2005.

Some carmakers, notably Williams' partners BMW, oppose the idea and want to retain V10s.

The FIA this week issued three alternative packages that the teams must choose from as the basis of regulation changes from 2005 aimed at cutting speeds on safety grounds as well as reducing costs.

Mosley said there was general agreement on aerodynamics and tyres but not on engines, with six or seven favouring one package and three opposed.

The Briton admitted it would be a serious concern if two or three manufacturers left the sport as a result of having engine regulations imposed on them.

But he added: "If we go for a restrictive engine, there are two manufacturers who might leave. If we allow the current levels of freedom to continue, there are two manufacturers who almost certainly will leave.

"It just depends if you believe them or not.

"My personal view is that if we go for the less expensive option, I don't believe anyone is going to leave."

Ferrari's Michael Schumacher has won 12 of the 14 races and secured his fifth title in a row, but Mosley said there was nothing basically wrong with the sport.

"I don't find it boring," he said. "I see that as a sporting phenomenon, rather like Muhammad Ali at his prime or (Pete) Sampras at his prime.

"It will change, teams go up and come down...If Michael Schumacher had not been there, we would have had a very exciting championship going on...I'm very optimistic for the future."