Toto Wolff has defended the controversial banning of mid-season driver helmet livery changes.

After the recent meeting of the F1 Commission, it emerged that the growing trend for multiple helmet colour changes will no longer be allowed.

The rule has now been enshrined in to the 2015 regulations, which read that drivers must race "substantially the same livery" at every race, on the grounds that they can be "easily distinguished from one another".

Sebastian Vettel, who has changed his colours no fewer than 60 times since debuting in F1, called the move a "joke".

Indeed, the introduction of the rule has been widely controversial, but Mercedes team chief Wolff thinks the timing may simply have been unfortunate, given the stalemate on other matters like engine rules and cost-cutting.

"This detail coming out of the F1 Commission made us look like we have nothing else to do than discuss driver helmets," he told Sky.

"As a matter of fact, the promoters are struggling a bit to promote their grands prix."

It is true that it is not just Bernie Ecclestone, the FIA and teams represented on the F1 Commission, but also sponsors and race promoters.

Wolff explained that while die-hard F1 fans are able to keep up-to-date with the drivers’ helmet changes, less regular viewers do not.

He said driver recognition has therefore become an "important" issue.

"So either you put big numbers on the car, which we didn’t like, or you make the driver more recognisable with the helmet," the Austrian explained.

"If the promoter thinks that it will help him sell tickets, I think that’s a good argument," added Wolff.