Red Bull have been "really encouraged" by the recent progress of their 2019 engine partners Honda.

The team will adopt a different approach to their relationship with Honda compared to the style of McLaren.

Honda supplied McLaren for three years between 2014 and 2016 before becoming Toro Rosso's exclusive power providers last season. In 2019, they will return to the sharp end of the grid with Red Bull, who are determined not to follow McLaren's perceived manner of micromanaging Honda.

"We have done the diverse opposite to McLaren," Red Bull boss Christian Horner told Sky F1. "We've said 'go and build the best engine you can, and then tell us what size radiators you want and we will make it fit'.

"We want Honda to go for power over packaging."

Who's powering who in F1 2019? Mercedes engines Mercedes, Force India, Williams Ferrari engines Ferrari, Haas, Sauber Renault engines Renault, McLaren Honda engines Red Bull, Toro Rosso

Red Bull have dropped Renault to switch to Honda, convinced their new partners have greater potential to deliver as much engine power as enjoyed by Ferrari and Mercedes.

"We see an awful lot of encouraging progress being made," added Horner.

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"Month by month, they are definitely closing the gap to Mercedes and Ferrari. What we are really encouraged by is the progress Honda are making.

"It's positive for F1."

Red Bull will run a Honda engine for the first time during pre-season testing at Barcelona, with the first test starting on February 18.

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