Toto Wolff has indicated that he thinks Formula 1 is changing the rules for 2017 at precisely the wrong moment.

After two easy title wins and almost unprecedented dominance for Mercedes in the 'power unit' era, the sport decided to turn a corner for 2017 with faster, wider cars and tyres.

Mercedes team boss Wolff says that radical change is now looming despite the fact that rivals including Ferrari and Red Bull are looking increasingly close to the leading pace.

"We are slowly getting back to a more normal situation in Formula 1," he said in Montreal.

"For two years we were in the fortunate position of being the dominant team, but now we see that the gap between the top three teams shrinks.

"All these years we were saying that if you leave the rules alone and don't change them, the balance of power would equalise and the fight would be closer. And so it happened. From the racing excitement side everything is now okay, but next year we are changing the rules yet again."

Mercedes remain top of the pile after the Canadian Grand Prix, leading Ferrari by 76 points.