Kimi Raikkonen is keeping his options open.

The Finn has yet to commit to Lotus for next season and Red Bull team principal Christian Horner has hinted that the door is still open for him to replace Mark Webber, who is soon retiring.

That would offer Red Bull a dynamic pairing of Raikkonen and three-time defending champion Sebastian Vettel — who are 1-2 in the Formula One championship with Raikkonen 38 points behind the German.

Even though Raikkonen's manager recently ruled out a move to Red Bull, the driver has not.

"There's always options until you sign something. I have nothing to say until there is something certain," Raikkonen said Friday after the second practice session of the Belgian Grand Prix, where he finished sixth. "I haven't heard anything really for a while. Obviously that's not the ideal situation but that's how it is."

Horner said he "wouldn't rule anything out at the moment" concerning Raikkonen because "he hasn't signed a contract with anyone yet."

Red Bull was widely tipped to announce Webber's successor at Spa, with Australian Daniel Ricciardo fancied for the seat, but the decision could now come at the Italian GP in two weeks' time.

"There's more options than you would possibly think," Horner said. "By Monza or shortly after we should be clear."

The remarkably consistent Raikkonen — who won the F1 title in 2007 — has scored points in 27 consecutive races.

With five second-place finishes to add to his win at the Australian GP, the 33-year-old must be wondering where he would be with a better car.

He also has internal issues to sort out with Lotus still owing him money.

Asked if he had not yet been paid, Raikkonen responded "not as I should" and "hopefully those things can (be sorted out) quickly."

Raikkonen has a reputation as an unflappable driver and is very popular with fans because of his cool demeanor.

Slumped in his chair, barely raising his voice, he answered questions from reporters with a pair of thick sunglasses on, even though he was sitting inside the team's motorhome.

"There's a lot of talk that I'm supposed to go to McLaren ... Ferrari one day, and Lotus the next day," he said.

He skipped Thursday's scheduled media briefing, with his team only saying that he was unwell. Raikkonen was evasive when asked if he was feeling better and what had been wrong with him.

"Yeah, fine," he said. "There's always reasons for things. I don't have to tell."

He was only slightly more forthcoming on what he wants before considering whether to commit to Lotus for next season.

"I know what (are) the certain issues that we have," he said. "As long as I get a place where all the things are as I want them."

The 2014 regulations set the sport's engineers the challenge of completing races on a lesser fuel load, and teams will switch from naturally aspirated 2.4 liter V8 engines to 1.6 liter V6 turbocharged hybrid Power Units.

"It's difficult to say which team will be the best," Raikkonen said. "The rules will change a lot."