As such, it makes determining a future on the grid difficult for the seven-time grand prix-winner.
Asked how long he expects to stay with the team, Verstappen told motorsport.com: "Difficult question. I don't know that either.
"Of course, I still have a contract for next year, and after that there are also new regulations, which haven't been signed off yet. So actually everybody is dealing with that question of what they are going to do. So I think I'm not the only one in that respect."
Red Bull's struggle to keep pace with Mercedes in the V6 Hybrid era means Verstappen is yet to truly feature in a title race as he approaches the end of his fifth season in F1.
The likes of Hamilton, Vettel and Fernando Alonso had been crowned world champion at similar points in their careers but, with time on his side at just 22 still, Verstappen is backing Red Bull to get back to the top.
"Everybody wants to win, in the end, so you always want to drive for the fastest team. But I believe that we can be there again as a team," he said.
"Of course they have already won four [titles], in a row, and we just started a new partnership with Honda and that just takes some time. That's why the goal should be next year. Then we really have to show it. And then we'll see what happens next."