Eric Boullier has claimed that McLaren will need some time to catch up with the top Renault-powered team in Formula 1 as the British outfit prepare to switch from Honda to customer Renault power for 2018.

Fernando Alonso, who is yet to sign a contract for next year, has said it is possible that McLaren will win races in 2018 because Red Bull have also managed to do that with Renault engines.

However, team boss Boullier is quoted by Spanish daily Marca as warning that catching Red Bull might take some time.

"If you have a 10-year relationship with a partner, you obviously have a different starting point to us," said the Frenchman.

"But we are in the process of building that relationship now. It will take some time, but we are motivated to do our best.

"We are McLaren, we exist to win, so we're going to do everything to achieve that."

Boullier also acknowledged that, after three seasons as the exclusive Honda partner, McLaren will now have a strong benchmark in the form of Red Bull next year.

"If you have the whole package - which means a good engine, the best car, people and driver - you should win. So for us the pressure is the same," he said.

"If another team has the same engine and you don't beat them, then you know something is wrong with the rest of the package."

McLaren sit ninth in the team rankings at the closing stages of the 2017 championship.