F1: After four World Championships Renault and Red Bull part ways

'Together we achieved outstanding results and in time our record will be recognised on its own merits'

Red Bull and engine suppliers Renault went their separate ways on Sunday as one of Formula One's most successful partnerships reached the end of the road in Abu Dhabi.

To mark the occasion, Renault Sport Racing managing director Cyril Abiteboul presented Red Bull boss Christian Horner with a squirrel soft toy -- a humorous nod to the 'Squirrel Irritable' nickname Horner has been known to use for the Frenchman.

"It’s on the pit wall, it spent the race with me. It’s a grumpy looking squirrel, an irritable squirrel," Horner told reporters.

The once-dominant partnership has been fraught in recent seasons, with Red Bull feeling let down in the V6 turbo hybrid era by a Renault engine that has lacked the power and reliability of rivals Mercedes and Ferrari.

Abiteboul and Horner have engaged in plenty of verbal sparring, with Red Bull seeking and failing to find another engine partner before Honda became an option.

Red Bull will hope for better with Honda next season while Renault, who are taking Red Bull's Australian driver Daniel Ricciardo with them, focus on their own factory team and clients McLaren.

"As one chapter closes, another one opens and we're already excited about 2019," said Horner.

Together Renault and Red Bull won 59 races with 160 podiums, 60 pole positions, 60 fastest laps and eight world championships -- four of them drivers' crowns with German Sebastian Vettel between 2010-13.

"In Red Bull we found a partner who would challenge for more of everything," said Abiteboul in a diplomatic Renault statement emphasising the positives.

"Together we achieved outstanding results and in time our record will be recognised on its own merits," he added.

"We wish Red Bull all the best for its next step and look forward to continuing our rivalry on track in the coming seasons."