Lewis Hamilton clinched his fourth Formula 1 world title with a run to ninth in Sunday's Mexican Grand Prix after a first-lap clash with championship rival Sebastian Vettel caused both racers to drop down the field early on.

Contact between the pair exiting Turn 3 left Vettel with front wing damage and Hamilton with a left-rear puncture, forcing both to pit early and drop to the back of the field.

Vettel fought his way back to fourth, while Hamilton struggled to make up ground at the same rate of knots, but was nevertheless able to make it through to ninth at the chequered flag and clinch his fourth world title.

Hamilton celebrated his fourth world title success in style with donuts on-track before lining his car up alongside the podium finishers, having received congratulatory messages from Toto Wolf, Niki Lauda and Brazilian footballer Neymar on his warm-down lap.

"I did everything I could. I had a good start, not sure what happened at Turn 3," Hamilton said.

"I tried as hard as I could to come back. Big thank you to my family, my team, Mercedes. I’m so proud to be a part of it.

"Honestly it doesn’t feel real man. This isn’t the race I want, 40 seconds behind. But I never gave up. I kept going right til the end.

"I just want to lift it up to my family, God and my team."

Hamilton becomes just the fifth driver in F1 history to win four world championships, following Juan Manuel Fangio, Alain Prost, Michael Schumacher and Sebastian Vettel.

Hamilton also stands clear as the most successful British driver in F1 history, moving ahead of Jackie Stewart on three world titles.