Ex-Formula One team owner Eddie Jordan has dismissed the idea of a breakaway series, saying the current championship is the "only credible solution".
Jordan says teams like McLaren and Williams will follow Ferrari's lead
The rival Grand Prix World Championship met nine of F1's 10 teams on Wednesday to sell its proposals.
But Jordan said teams would follow Ferrari's lead in signing up with F1 commercial boss Bernie Ecclestone.
"A vast majority of the teams, once you've got Ferrari on your side, will all side with Bernie," he said.
Jordan, speaking on BBC Radio Five Live, admitted that to make his remarks before Wednesday's meeting was "a bit premature".
But he said the GPWC would have to come up with "a hugely beneficial deal to attract the teams to go with them rather than Bernie Ecclestone".
Jordan, who has sold his team to Canadian billionaire Alex Shnaider's Midland Group, said: "Bernie Ecclestone is the only credible solution because the private teams would have great problems believing that the manufacturers will look after their needs and cares.
"Bernie has looked after us almost like a godfather figure, in a tough way, but a fair way."
The GPWC - which comprises DaimlerChrysler, Renault, BMW, Honda and Toyota - was set up to safeguard the manufacturers' interests in F1.
It wants to secure more money for the teams, create a more transparent environment, ensure long-term stability and attract the widest possible audience.
It is threatening to set up a rival championship in 2008 if its wishes are not met, a plan that is widely believed to be a way of forcing Ecclestone's hand in the battle for more money for the teams.
But Ecclestone's recent deal to ensure Ferrari remains with F1 until at least 2012 is likely to mean no rival series would be viable.
As by far F1's biggest draw, Ferrari's presence would almost certainly guarantee the championship they were involved in would have the biggest following in the event of any split.
Ecclestone has already offered the other nine teams an improved financial deal, which will increase their share of F1's entire commercial income from an estimated 23% to around 50%.
Max Mosley, the president of motorsport's governing body the FIA, said last week that Ecclestone's offer would give the teams "a substantial income".
GPWC will tell them it plans to make 75% or 80% available, an offer that Mosley, a long-time partner of Ecclestone, says makes a new series economically impossible.