Mercedes non-executive chairman, Niki Lauda, has said that a new two-year deal with Nico Rosberg is all but signed.

The world championship leader, whose contract runs out this year, has yet to agree a new deal with the team for which he has driven for seven years.

Appearing at the Goodwood Festival of Speed on Sunday, the German was giving little away having handed over negotiations to Gerhard Berger in order that he can focus on the job in hand, the title fight.

Speaking to Bild however, Lauda was confident that the deal will be done.

"We have pretty much agreed on a new two-year contract but still have to work on the details," said the Austrian.

Asked if the contract was a present for Rosberg, who celebrated his 31st birthday on Monday, Lauda said: "No. He has worked hard to earn it."

The situation will be watched with interest by rival drivers, aware that Mercedes is the one team that virtually guarantees them a serious shot at the title.

Consequently, with Rosberg almost certain to remain with Mercedes, focus shifts to Ferrari and Red Bull. Whilst the Austrian team has contracts with both Max Verstappen and Daniel Ricciardo, the Australian has admitted that he might be interested should a vacancy arise at the Maranello outfit.

"I understand if they were to make a change I'm on their list," he told Autosport.

"There haven't been any calls saying, 'We're going to get rid of Kimi, we want you, can you do it with your contract?' this or that," he admitted. "I'm aware they'd be interested, I don't blame them... but other than what's been said in the media, there's been nothing else, honestly."

Ferrari president Sergio Marchionne, speaking in Baku, said he wants to retain the Finn, but that it is up to Raikkonen to deliver the goods.