The three-time world champion has been with the Milton Keynes-based outfit for eight years, since a sudden promotion from Toro Rosso to replace Daniil Kvyat.
“It’s like anything in life, you can’t force somebody to be somewhere just because of a piece of paper,” he told media after the Saudi Arabian Grand Prix.
“If somebody didn’t want to be at this team, then we’re not going to force somebody against their will to be here.
“And that applies whether it’s a machine operator or a designer or somebody in one of the support functions. That runs through the business,” Horner continued.
“Being involved in a team like this involves commitment and passion. And Max has that. We’ve seen that.
“He’s been here since he was 18 years of age. And I have no doubt of his commitment and passion going forward. But that’s the way it is.”
For now, it seems as though any Verstappen move is off the cards, after Red Bull advisor Helmut Marko affirmed his commitment to the team following a meeting with Red Bull GmbH managing director Oliver Mintzlaff.
Their attention will now turn to the Australian GP in two weeks' time, as they attempt to take three consecutive one-two finishes to open the Formula 1 season.