One of the three Canadian GP stewards said they decided not to penalise Sebastian Vettel for his post-race antics of last Sunday in Montreal.

Hans-Gerd Ennser, under fire for the time penalty that cost Ferrari's Vettel victory, says the FIA panel actually gave the German as lenient a punishment as possible.

"It could have been 10 or 20 seconds or a stop-go penalty," he is quoted by Kleine Zeitung.

"The five second penalty is the least penalty for such an offense."

Ennser also explained that the stewards decided not to add to Vettel's troubles by penalising his post-race antics, including boycotting 'parc ferme' and switching the positions of the number 1 and 2 marker boards.

"We were told about these incidents, but we thought that because of the high emotions and the great pressure Vettel was under, we would not impose any further penalties," he said.

Another Canadian GP steward, Mathieu Remmerie, also defended the imposition of Vettel's time penalty.

"The rules are what they are, and we are here to apply the rules," he told the Belgian news agency Sporza.

"The discussion as to whether the rules need to be adjusted may of course take place," Remmerie added.

"As a motor sport enthusiast, I naturally also like to see a great race. Do some regulations go too far in certain cases? Maybe yes.

"If you compare motor sport with 10 to 20 years ago, then a lot has been improved, but it was always also at the initiative of the teams themselves," he said.

Remmerie admitted he was "slightly shocked" by the "huge media attention" since the controversial decision last Sunday.

But he said: "There will always be commotion around certain decisions."