The energy drink squad took its first win of the season last time out at its home race in Austria, as Verstappen beat Charles Leclerc in a late-race scrap.
The victory for Red Bull means they claimed a win before Ferrari, as Mercedes dominated the first eight races of the year.
But Verstappen affirms that the team can't become complacent after the winning, admitting that there is still plenty to be done in order to be consistently at the front of the grid.
"We still need to work hard," he said. "We won a race, but it doesn't suddenly mean that we are the dominating team. We still need to step up our performance more."
Verstappen added that he can't predict how the car will perform at the British Grand Prix this weekend, with on-track action the only way to find out.
"We'll find out on Sunday. It's always the same, I don't know what's going to happen, if I did then it would be great," Verstappen commented.
"But I don't know where we are at the moment. Of course, we are confident and you think you can do a good job, but also with Mercedes, we don't know where they are, they don't know where Ferrari are.
"You don't know until you go out onto the track and see. I always say to myself that it's better to just find out and not talk too much about it."