Sauber will take a decision "quite soon" on who will fill its second Formula 1 seat for 2019 and partner Kimi Raikkonen, according to team principal Frederic Vasseur.

Sauber confirmed earlier this week that current Ferrari driver and 2007 world champion Raikkonen would be returning to the team where he made his F1 debut in 2001, signing a two-year deal, starting next season.

Singapore #6 - 5 Talking Points

Raikkonen's arrival sees him swap places with Charles Leclerc, who will move from Sauber to Ferrari for 2019, but the team is yet to make any decision on its second seat, currently held by Marcus Ericsson.

Speaking in Singapore, Sauber team principal Vasseur said he needed time to think following the rush of the deal to sign Raikkonen, which was finalised in around a week, but added it would not be long until the second driver was decided upon.

"Please, the last two weeks for me have been a bit in a rush on the driver market, so if I can have some days off from this?!" he said.

"After Singapore, we will sit down with all the persons involved in the discussions, and we will take a decision quite soon.

"I think it’s also good for the team to have a clear answer, but it will be soon."

The race to clinch the second seat looks to chiefly be between Ericsson, who has links to the team's owners, and Ferrari youngster Antonio Giovinazzi, who is appearing in a number of practice sessions for Sauber between now and the end of the season.

Ferrari team principal Maurizio Arrivabene was relaxed when asked about Giovinazzi's future, saying: "You will see about the future of Giovinazzi I think in the next few weeks, so I’m not concerned at all."

While Ferrari is known to have some sway in the decision thanks to its links to Sauber's title sponsor, Alfa Romeo, it is not believed that the Italian marque played a part in Raikkonen's move to the team.

Other current free agents for 2019 include Stoffel Vandoorne, Esteban Ocon and Pascal Wehrlein, the last of whom will be released from Mercedes at the end of the season.