Ricciardo said he had a few sleepless nights making up his mind whether to move to Renault. File photo: Tamas Kovacs / MTI via AP

Spa-Francorchamps, Belgium - Daniel Ricciardo has justified his surprise decision to leave Red Bull for Renault in 2019 by saying he simply needed a change of scenery - but team-mate Max Verstappen was not convinced.

"If it is a change of scenery, I'm not sure if it's the best scenery to go to," the 20-year-old Dutchman told reporters at the Belgian Grand Prix on Thursday.

Ricciardo has won two races with Red Bull so far in 2018 but will join a team further down the pecking order that last won a race a decade ago, even if it is moving back up.

Red Bull will switch from Renault to Honda engines in 2019, and Ricciardo's decision has been seen by some as a sign that he was not convinced by what the Japanese manufacturer could offer.

'No bad blood'

Ricciardo denied he had felt 'unloved' at Red Bull, although Verstappen is held up as a champion-in-waiting at that team, and said there were no hard feelings.

"To be clear, there was no falling out, no bad blood with anyone in the team, the bosses or anyone," he told a news conference, adding that it had not been an easy decision to make. "I felt I was ready for a change, a new challenge and just for me personally some fresh motivations; a few sleepless nights for sure trying to come up with the best conclusion for myself."

He said he had still been unsure during the Hungarian race weekend at the end of July but made up his mind during the following days.

"Once I pulled the trigger I felt comfortable with it. It feels right," he added. He agreed Honda still needed to prove itself, but said Renault also contained an element of risk and the key factor had been him "wanting to have a change of scenery" after 10 years in the Red Bull family.

Verstappen, who has one win this year, suggested Ricciardo should have waited.

"Of course everybody has moments in their career where you're frustrated or you're not happy with the current situation," he said. "I think everybody here wants to win races or wants to win championships but sometimes it's not like that and you have to really be patient and work hard for it."

Verstappen and Ricciardo, who will be replaced by Frenchman Pierre Gasly, got along well as team-mates and Ricciardo said he would miss that.

"If he starts calling Pierre the best team-mate he ever had my heart will be broken," he said, grinning.