Renault may soon have space for another customer team in Formula 1, but a reunion with Red Bull could well be vetoed by star driver Max Verstappen.
Red Bull and Renault was a title-winning combination between 2010 and 2013 as Sebastian Vettel dominated the sport.
However, the partnership soured as the dawning of the V6 Hybrid era saw Red Bull's crown slip and Mercedes take over as F1's dominant force, with a sixth straight title double a near certainty this year.
As such, Verstappen is yet to properly feature in the title race, despite coming towards the end of his fifth season in F1, most of which have come in the Red Bull cockpit.
With Red Bull having jumped ship to Honda this year and taken two race wins, the team are certainly happy with their lot, although the Japanese marque is yet to commit to F1 in 2021 and beyond.
Marko has previously suggested that Red Bull would quit F1 if Honda were to depart, and he unequivocally ruled out a reunion with Renault in any case.
He is quoted by Auto Motor und Sport: "As long as Max Verstappen is still driving for us, there will never be a Renault engine in our car again!"
Marko has praised Honda's efforts throughout 2018, with Red Bull's struggles early in the year put down to failures on the chassis side.
With upgraded engines and fuel set to be used in the Japanese Grand Prix next week, Red Bull hope to deliver a home win for Honda.
McLaren and Toro Rosso have failed to score a single point at Suzuka when using Honda engines since the brand's return to F1 in 2015, with three of the four races seeing a Honda-powered car finish 11th.