Renault F1 boss Flavio Briatore attended the hearing in Monaco

The International Automobile Federation (FIA) found Renault guilty of breaching F1 regulations by having rival team McLaren data in their possession.

But the sport's governing body, who will publish their detailed decision on Friday, opted to impose no penalty on former world champions Renault.

The ruling could see Fernando Alonso, who won the F1 world title with Renault in 2005 and 2006, return to the team.

It is thought Alonso, who quit McLaren at the end of the 2007 season after a turbulent year with the team, has been waiting on this verdict, though the Spaniard has also been linked with Red Bull.

We thought it wasn't appropriate to put the sort of penalty on any team that we suffered McLaren chief executive Martin Whitmarsh

"I understand the evidence of Charlie Whiting, the FIA technical director, proved crucial," said BBC Radio 5 Live's David Croft of the FIA verdict.

"He was satisfied that no McLaren intellectual property had made its way onto the design.

"Renault's actions in admitting the offence also counted in their favour.

"But the FIA have reserved the right to call Renault back in the future should new evidence come to light."

An FIA statement read: "The World Council found Renault F1 to be in breach of article 151c of the International Sporting Code, but imposed no penalty.

"Detailed reasons for this decision will be issued on December 7, 2007."

And asked by 5 Live to explain why Renault had been found guilty but not punished, FIA boss Max Mosley said: "When people have seen the reasons they will understand.

"I wouldn't say (it was an easy decision to make), it took several hours, but we'll explain everything tomorrow."

Renault reacted to the decision through a statement from team boss Flavio Briatore, who said: "I would like to thank Renault, our title sponsor ING and all our partners for their wholehearted support during this sensitive period.

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"I also wish to pay tribute to the team, which has handled the matter with integrity and dignity.

"We are pleased that we can now focus fully on our preparations for the 2008 championship."

McLaren chief executive Martin Whitmarsh said: "We made the case to the World Motor Sport Council that we thought it wasn't appropriate to put the sort of penalty on any team that we suffered.

"We made that very clear, we weren't pushing for that, but we believe it to be a serious case."

In July, McLaren were found guilty of being in unauthorised possession of technical information belonging to Ferrari.

But when fresh evidence did surface, McLaren were found guilty in September and hit with a sporting record �50m fine, while the team were stripped of all constructors' points for 2007.

And McLaren face further scrutiny on Friday after the FIA said it would investigate further to ensure that no Ferrari data appeared in next year's car.

The Renault case surrounded engineer Phil Mackereth, who joined the team from McLaren in September 2006 and took with him information belonging to McLaren on 11 floppy disks.

The information contained details of the McLaren fuelling system, gear assembly, oil cooling system, hydraulic control system and a novel suspension component used by the 2006 and 2007 McLaren cars.