The FIA should keep working to end the 'grey areas' in the engine regulations.

That is the view of Renault team boss Cyril Abiteboul.

This week, we reported that the governing body has clamped down on various loopholes in the rules, with one engineer telling Auto Motor und Sport: "We have received more technical directives for the engine than ever before."

And F1 race director Charlie Whiting admitted: "We have become stricter in all areas where the engine manufacturers could theoretically overstep the mark."

Abiteboul welcomes the moves, declaring that Renault was already not exploiting those grey areas.

"Since the 1980s, Renault's policy has been to respect the rules in their wording and in their spirit," he said.

"The actions of the FIA are going in the right direction, but there are still ways to exploit the rules in certain areas to the limit."

With that in mind, Renault technical boss Nick Chester says the team has made progress with the engine over the winter.

Abiteboul has even put the leap at up to 50 horse power.

"The new engine has more power," Chester confirmed to El Confidencial. "We are very happy with it.

"I can't say how much power we have, but it's a good jump. I think Renault has approached Ferrari and Mercedes."