Horner sceptical of F1 engine breakthrough

Formula One is nowhere near an agreement to ensure all teams have access to competitive and cheaper engines from 2018 and time is running out, Red Bull principal Christian Horner warned on Friday.

The governing International Automobile Federation (FIA) has asked the four engine manufacturers to come up with a plan by the end of April to ensure no team is left without power units in future.

"I think it's a complex situation but, fundamentally, there were four criteria that were requested by the governing body to be met to ensure stability moving forward," Horner told reporters at the Chinese Grand Prix.

"As we sit here now, we are not anywhere near having met any of those criteria," he added.

"I think unfortunately what will happen, as is often the case with these things, (is that) time will run out at the end of the month and nothing will be achieved - nothing will change."

The FIA and the sport's commercial supremo Bernie Ecclestone have threatened to introduce a cheaper independent engine if manufacturers fail to reach an agreement.

The main criteria were for a power unit supply to cost 12 million euros ($A17.5 million) per season, for the supply to be guaranteed, performance gaps to narrow and engines to be louder.

Red Bull struggled to secure an engine for this season after falling out with long-term engine supplier Renault.

They eventually reached a deal to continue with the French manufacturer after Mercedes ruled out a supply, Ferrari offered only an old engine and Honda's interest was vetoed by sole partners McLaren.

Mercedes motorsport director Toto Wolff said all parties were working hard to find common ground by the deadline but it was impossible to satisfy everyone.

"Christian isn't so happy. But I think we need to come up with a solution until (by) the end of April," he said.

"We need to ratify those regulations and, at the moment, everybody is working very hard to at least find the smallest common denominator."