Sebastian Vettel says it is "clear" that he wants to win the 2019 world championship.

The German has taken a lot of heat in the paddock as he and Ferrari failed to secure the crown despite having a competitive car last year.

But Vettel, who appeared for the race of champions event in Mexico last weekend, says they are ready to try again.

"The ingredients are there, now it's up to us to do the job," he is quoted by La Gazzetta dello Sport.

There have been changes at Ferrari over the winter, with Mattia Binotto taking over as boss and Charles Leclerc replacing Kimi Raikkonen.

Vettel said of 2019: "It will be a great challenge. What we want to achieve I think is clear.

"The opponents? Let's see how the first tests go, as at this time of the year everything is hidden. When we see the cars on the track we will know better and at the first race we will know for sure."

Vettel made obvious mistakes in 2018, but he says the real problem is that the Ferrari was not quite as good as the winning Mercedes.

"I think we need a stronger package," he said.

"We certainly had our moments last year when we had strong races, but we also had races which weren't very strong.

"I think overall it's the speed that decides and I think more often than not we were lacking a little bit of speed.

"But we're working very hard and the motivation is there to do that final step that is still missing," Vettel added.