Sebastian Vettel and Nico Rosberg
Vettel is happy to race with Ferrari in 2017 season Reuters

While Nico Rosberg's sudden retirement has caught the Formula One fraternity and his constructors Mercedes off guard, Sebastian Vettel has pledged his allegiance to Ferrari amid rumours that the German driver will replace his compatriot at Silver Arrows.

Five days after winning the 2016 F1 driver's championship, Rosberg shocked quite a few by announcing his retirement from the sport. While the 31-year-old maintained that winning the title was his dream, he also revealed he was not ready to get committed to defending his title in the 2017 season.

The Mercedes camp are reportedly looking for a replacement as soon as possible and the top management wants to announce their new drivers who will team up with Lewis Hamilton, before the end of the year.

Speculations were rife that Mercedes was willing to contact either Vettel, who still has a year left in his contract with Ferrari, or Fernando Alonso who is currently signed up with McLaren. Notably, both the drivers are former world champions and given Mercedes recent domination of the sport, one of them racing for Silver Arrows will possibly give the German constructors the control over the rest in the coming years.

However, Vettel dismissed rumours and said his teammate Kimi Raikkonen and himself had no intentions of leaving Ferrari and that they were upbeat about the upcoming season, which starts in Australia on 26 March.

Also read: Check out the 2017 Formula 1 calendar

"I think it is not a big secret that both myself and Kimi have a contract for next year. So it should be clear," Vettel, the four-time world champion, was quoted as saying by the Reuters.

"I don't know what is their [Mercedes] plan. But for us we look after ourselves for next year, there is lots of things changing so we're quite busy ourselves. We're very positive for next year."

Meanwhile, Mercedes boss Toto Wolff has revealed that their team is not looking at big-name drivers as Rosberg's replacement. However, he revealed that he has been receiving calls from "80% of the F1 drivers" as the race for the sought-after spot has heated up.

"It is not my intention to interfere with Ferrari's internal issues. And I don't even know if Sebastian really has the intention to come to us. It's the same thing [with Alonso]: what would Ferrari and McLaren do without Vettel and Alonso in December? Or Williams without [Valtteri] Bottas? [That] option is the one I like the least," Wolff told Gazzetta Dello Sport, as quoted by the AutoSport.

With the option of luring big names ruled out, it is expected that Mercedes protege Pascal Wehrlein will replace Rosberg. The 22-year-old, who drives with a German license, won the Rookie of the Year award for his performances at Manor in the 2016 season.