Pierre Gasly says he is in formula one "clearly to win".

Despite it being only his first full season on the grid last year, 22-year-old Frenchman Gasly was chosen to replace Red Bull's Renault-bound Daniel Ricciardo for 2019.

He will be paired with Max Verstappen this year but Dr Helmut Marko insists Gasly will not be the "number 2" driver.

"This will be my second season in F1 so I know I still have things to learn," Gasly told RMC.

"I was in Mexico for the race of champions and I talked to Vettel to ask him about when he really felt at his peak in terms of developing. He said it was 28 to 30.

"We are constantly developing with experience, so I know that I am going to improve myself," Gasly continued. "But if I'm in F1, it's clearly to win and to one day go for the world championship.

"It will take the time that it takes to get that experience, but to be world champion you have to beat the best and Max is clearly one of the best at the moment.

"So for me it is a superb opportunity and comparison," he added.

Red Bull and Verstappen are bullish about their title chances for 2019, but Gasly says he is not sure how competitive Red Bull will be.

"I do not have specific goals for the season yet, because we do not know how competitive the car will be," he said.

"The regulations have changed, and we have changed our engine supplier. We only have three power units for 21 grands prix, and that's a difficult situation. If I am not mistaken, last year we (Toro Rosso) used eight engines.

"But if Red Bull builds a good car, and we get the chance to compete for the podiums and for victories, I will try to use it," Gasly said.