Kimi Raikkonen should not be regarded as 'number two' to teammate Sebastian Vettel at Ferrari, according to Mika Salo.

However, former Ferrari driver Salo admits that fellow Finn Raikkonen has a tough challenge ahead of him to return to his title-winning days.

"At any rate, I do not see Kimi as the second driver," Salo told Finnish broadcaster MTV.

"But if he wants the championship, first he has to beat Vettel. Then we will see if it is enough."

Asked if he thinks that 2016 will be the 36-year-old's last F1 campaign, former Toyota and Sauber driver Salo answered: "It's hard to say.

"But I do think Ferrari was clever in keeping both drivers this season, because continuity is important. As it's also good that the drivers get on well with each other."

Raikkonen and Vettel finished fourth and third respectively in 2015's driver standings behind the Mercedes pair of Lewis Hamilton and Nico Rosberg.