Max Verstappen has no issue with a possible Carlos Sainz Jr. move to Red Bull, Helmut Marko has insisted.

The 23-year old, who joined Renault from Red Bull's junior team Toro Rosso during last season, will be replaced by Daniel Ricciardo in 2019 in a surprising switch.

The Australian's departure comes after his apparent dissatisfaction with playing 'second-fiddle' to Verstappen, who was recently handed a lucrative new contact.

The search for a high-profile replacement has begun, with Fernando Alonso and Finnish driver Kimi Raikkonen both linked.

It would seem, however, that Sainz, already in the organisation's ranks, and having previously partnered Verstappen at Toro Rosso, would appear to be a more natural choice.

The pair are rumoured to have endured a rocky end to their relationship at Toro Rosso, before Verstappen's promotion.

It has even been reported that the Dutchman had vetoed the suggestion of Sainz as Ricciardo's successor.

But Red Bull chief Helmut Marko has denied the speculation and insists Verstappen will not have any influence on who will partner him next season.

"The rumours are wrong," Marko said, per The Express.

"Red Bull is the one that decides about drivers.

"Daniel called me on Thursday to inform me of the decision to leave the team at the end of the season.

“He spent most of his career at Red Bull and told me he wanted a change, that's right.

“Now we will have to think about who will be Max Verstappen's teammate.”

Although Sainz is currently without a seat in 2019, it is unlikely he will still be a free agent by the time next season starts.

McLaren are reportedly also interested in his services but Sainz has said he is open to returning to the Red Bull fold.

"At the moment I'm still a Renault driver," he told Auto Motor und Sport.

"If Red Bull asks me to come back, that would of course change. I owe Red Bull a lot. The mutual respect is great.

"I also have a very good relationship with Helmut Marko. It's thanks to him that I'm in F1."