The Reds could be confirmed this season's Premier League champions against Tottenham today.
Van Dijk said: "In my opinion, the story is not yet finished. The club is very ambitious, the plans for this summer sound good. There is still a lot to achieve here.
"Whatever is going to happen with players coming or leaving, I think this is going to be a very important summer for the club. I am convinced that the club management see it that way too - and we have to trust that they are going to do that in a good way. So that we can also play for prizes in the coming years.
"Arne (Slot) is doing a great job. (Jurgen) Klopp was - and is - a legend at this club, but the new coach has added some new touches in his own way, without immediately turning everything upside down.
"Next summer will actually be the first transfer window in which Arne can really make his own choices. That combination of things makes me really confident about the next two years."