The Dane wants to remain at Renault next season and had been hoping that the French car manufacturer would confirm its intentions before the end of this month.

But after team principal Fred Vasseur said last week that a decision on drivers was delayed – with previous targets Sergio Perez, Stoffel Vandoorne and Valtteri Bottas all likely unavailable – the situation is no longer as clear.

Speaking at the Singapore Grand Prix, Magnussen said that reports he had issued an ultimatum to Renault to decide by the end of this month were "not necessarily true".

However, he admitted that there was an element of frustration that matters were dragging on – as at some point he would need to start looking at options elsewhere.

"I don't know what is going on behind the scenes," explained the Dane. "I have read in the press that there has been a delay and that the decision could take a long time. Yes, it is [frustrating].

"I was hoping for a decision between these two races, but clearly it hasn't come and things are taking longer than I had hoped for. I would be a bit more relaxed if that was the case but that is not what I have. So anyway, that is how it is."

Magnussen insisted that there was no reason for him to be worried about the ongoing delay in finding out what was happening, but said that life would be easier if he knew.

"It is not too bad," he explained. "I feel quite relaxed about it, even though my future is uncertain I feel quite relaxed. I can't do any more than I am doing. I do my best and if that is not good enough then so be it.

"Hopefully there will be a decision at some point, otherwise I will take it. I am a racing driver and I need to race. I can't wait around until one week before the first test. That is not an option for me. We will see what happens."

Vasseur has been clear that he wants drivers to be a focal point of motivation for team members, and there have been suggestions he is not convinced that Magnussen delivers enough to be a team leader.

But Magnussen said he had spoken to Vasseur about the job he was doing, and said there had been no suggestion his attitude was wrong.

"I have asked him and he told me, 'I cannot complain'. Whether that is true or not. I don't know. I am doing my best, and I feel like I am on top of my game. I don't feel there is a lot more I can do.

"Whatever it will be I can say that I have done my best and hopefully that is good enough. But I don't know what is holding back the decision. We will see what happens."