Helmut Marko believes it will be "hard" for Daniel Ricciardo to celebrate any Formula 1 victories with his traditional 'Shoey' celebration in the near future after deciding to leave Red Bull for Renault in 2019.

Ricciardo announced earlier this month he would be leaving Red Bull at the end of the season in order to make a shock switch to Renault for the 2019 season, partnering Nico Hulkenberg.

The decision came as a shock to the F1 paddock, with Ricciardo previously thought to be on course to sign a new contract with Red Bull. Pierre Gasly will take his place at the team from next season.

Speaking for the first time since the announcement on Red Bull's in-house TV channel, Servus TV, Marko revealed that both he and Red Bull owner Dietrich Mateschitz were expecting Ricciardo to sign a new contract on the Tuesday following the Hungarian Grand Prix.

"I cannot understand the change. That was a very strange story," Marko said on the TV show, via Auto Motor und Sport.

"The negotiations were difficult. On Wednesday before Austria, I sat together with him for two hours and we agreed. In Hungary, he said to both me and Mr. Mateschitz that everything fits, and he'll sign on Tuesday at the test. He did not do that.

"On Thursday afternoon I got a call. He was funny in his voice. I told him: 'Get to the point! We are adults.' Then he said: 'I'm going to Renault.'"

Marko said he felt two of the reasons behind Ricciardo's decision were a lack of confidence in Red Bull's decision to link up with Honda as a power unit supplier from 2019, as well as the contract offered by Renault, before adding he doubted the Australian would be celebrating any race wins in the upcoming years.

"I can only assume that he does not believe in the Honda project and that Renault offered him a very high amount," Markos said.

"But I think Shoeys will be hard for him in the near future."

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