Thursday's confirmation that Romain Grosjean is staying at Haas has taken away one of Hulkenberg's main options, although the German downplayed the news, insisting that he knew well in advance that the door had closed.

The obvious remaining possibilities are at Alfa Romeo, where Antonio Giovinazzi has yet to be confirmed, and at Williams, after today's announcement from Robert Kubica that he won't stay with the team.

Hulkenberg began his F1 career with the Grove team in 2010.

"I think you see and understand for yourself what's available, which seats and which not," Hulkenberg said. "I think that's pretty obvious. Right now it's to a big extent out of my control, out of my hands.

"We just need a bit more time. I think there are still possibilities and realistic chances, but in this game you can never be too sure."

Asked if he was disappointed by the news from Haas, he said: "No, because I didn't pursue that deal, and we didn't go ahead, we didn't agree, we didn't get together with Haas.

"Haas was definitely an option, and we were talking, that's definitely not a secret. We just didn't get together on this occasion, we couldn't agree a deal.

Alfa Romeo remains an possibility for Hulkenberg, who is a favourite of team boss Fred Vasseur, for whom he drove in both F3 and F2. He acknowledged that the connection was useful.

"We've known each other since many years, he's obviously the guy that brought me here [to Renault] as well, that I did the deal with ultimately. I guess it doesn't hurt."

Hulkenberg also acknowledged he would have to consider the current struggles of Williams should he be offered the chance to return to the team where he started his career.

"As much as I want to continue in F1, for me it needs to make sense. It needs to be sensible, it needs to be the right deal. I'm not desperate to stay in F1 and just take anything.

"I'm not disregarding or disrespecting Williams now, I mean in general, globally, even with Haas, that is the most important thing for me."

Regarding the outside chance of taking on Max Verstappen at Red Bull should the team look outside its current pool of drivers he said: "Couldn't say no to that car. So I guess you'd have to take it! They go together. It would be obviously a big challenge. As we know, Max is a killer and he's one of the fastest."

Hulkenberg insisted that he's not yet looked at potential opportunities in other series, such as Formula E.

"Honestly now, it's not just what I'm saying, I haven't looked into these options. I think there has been interest from inside people of this series, but I haven't really pursued that.

"My head is very much here still. And that would be only something I would consider really a little bit down the line if I knew things weren't going ahead here. But for now, no."