Red Bull's Christian Horner has admitted that "the lure" of another team was too much for Sebastian Vettel.

The world champion parted ways with Red Bull this morning, and has been strongly linked with a move to Ferrari.

"I think the lure of another team that's brightly coloured has come up and it's a point in his life and career that he's felt the timing is right for him," Horner is quoted as saying by ESPN.

"We obviously respect that decision and rather than looking to hold a driver against his will, if somebody's heart isn't here, it's better to reflect on the good times and look forward. I think he just fancied a new challenge.

"He's decided that his heart is somewhere else and we look back with a huge amount of pride about what we achieved together and it wouldn't be right to hold him back. If someone's heart isn't in the team it's better to release them. We now face a new era within the team."

Fernando Alonso is reportedly on his way out at Ferrari, paving the way for Vettel's arrival.