Sebastian Vettel has admitted that Baku was "the worst moment" in his failed 2017 championship challenge.

While Ferrari's end of season unreliability was arguably more to blame, German Vettel takes full responsibility for having lost his cool and crashed deliberately into Lewis Hamilton during a safety car period in Azerbaijan.

"The worst moment was Baku," Italy's Mediaset quotes him as saying.

"I ruined the race by doing something unnecessary.

"Singapore and Japan didn't go well either, but it's different because you can't control something that doesn't depend on you."

However, the quadruple world champion said that Hamilton - who now also has four drivers' titles - fully deserves his crown.

"There is no doubt about his ability and speed. He is very quick and he makes few mistakes," the 30-year-old said.

As for what he has learned from 2017, Vettel concluded: "Now I think differently than in the past, or in a slightly wiser way. I hope this will allow me to do better."

The new championship gets underway next March.