Lewis Hamilton is concerned a dangerous precedent has been set after Sebastian Vettel was not penalised for driving erratically ahead of the first Safety Car restart at the Azerbaijan Grand Prix.

The Safety Car made two appearances during Sunday's race and the first came at the end of lap one after a series of accidents left cars and debris strewn across the track. Vettel was leading the race from Hamilton at the time and as the Safety Car returned to the pits on lap five ahead of the restart, it was down to the Ferrari driver to control the pace of the pack.

Baku's long pit straight means restarts have the potential to be dramatic in Azerbaijan as the lead car has to avoid overtaking the Safety Car before it gets to the pits while also guarding against the car behind getting a slipstream down to Turn 1. In this instance Vettel left his acceleration relatively late, which is allowed under the regulations, and spent a long period of time warming up his tyres by accelerating and braking before finally pinning the accelerator to restart the race.

Article 39.13 of the sporting regulations states "in order to avoid the likelihood of accidents before the Safety Car returns to the pits, from the point at which the lights on the car are turned out drivers must proceed at a pace which involves no erratic acceleration or braking nor any other manoeuvre which is likely to endanger other drivers or impede the restart." While it is very much open to interpretation by the stewards, it is this part of the regulations that Hamilton believes Vettel was in breach of.

"The rules are that, when the Safety Car goes, you are not allowed to start and stop, start and stop," he said. "You are not allowed to gas and then brake and you are not allowed to fake the guy behind. Naturally, if there was not that rule that is what you would do because it would eventually catch them sleeping. But you are not allowed to do that.

Sebastian Vettel led the pack at the first Safety Car restart in Baku. Dan Istitene/Getty Images

"You are allowed to weave but you are not allowed to start and stop, start and stop -- that's against the rules. If you look at all the times and examples -- particularly the four restarts I did last year -- I didn't do that and I abided by the rules.

"In Australia, Sebastian accelerated and then braked and I nearly went up the back end of him. In Baku he did it like four times. I need to speak to Charlie [Whiting, FIA race director] because I don't fully understand it. As far as I'm aware Charlie passed it on to the stewards and the stewards didn't do anything about it. I think the stewards supposedly said that all the other cars were doing it, but we are the leaders so it cascades down and it's a domino effect. So what the first car does, everyone does the same thing."

Whiting confirmed the FIA stewards had looked at the restart, but believed there was nothing wrong with Vettel's conduct.

"I think he [Vettel] controlled it very well but it's up to the leading driver to say when we go," Whiting explained. "Unlike some other series, they have an acceleration zone, a place where you can accelerate. You can't do it before or after that. Once it goes green, the Safety Car comes into the pits, it's up to the leader to decide when he is going to go.

"This is a tricky place, they catch the Safety Car too early if they go too quickly. I think Seb controlled it well. There was a bit of a complaint from Lewis that he wasn't going at a constant rate, but if you look down the field, there's a few places where that happens. To expect them to go at one speed doesn't happen. So long as no one does anything dangerous, we're happy."

But Hamilton said he would raise the issue at the next drivers' briefing at the Spanish Grand Prix as he is concerned Vettel's actions set a dangerous precedent for F1 and the categories below.

"If the rules aren't clear, that now sets a precedent, so anyone who is leading a grand prix under a Safety Car can start and stop -- and that goes the same down to Formula 2, Formula 3, Formula 4 because they are not going to get penalised. I don't understand, because the rule is that you're not allowed to. So I need to get that rectified when we next have the briefing, because clearly they don't care about it and if that's the case we will see more of it.

"I will expect that from him next time I'm racing and I will prepare for it. If you noticed, I already put my car to the right to avoid a collision because he was starting and stopping, otherwise I would tuck in behind."