Jenson Button is a key member of the McLaren-Honda project, according to his current teammate Fernando Alonso.

It is no secret that the Anglo-Japanese collaboration is considering replacing Button with McLaren youngster Stoffel Vandoorne for 2017, with the young Belgian warning that other teams are expressing interest in him.

However, 2009 world champion Button, 36, has looked impressive at McLaren since Alonso joined the team last year, even scoring more points than the Spaniard in 2015.

"Last year it was difficult to have many races when we had the same conditions because we always had some engine problems. I think we used 11 or 12 engines in the season. This year is a bit fairer, and yes, he is fast," Alonso, who is staying at the team for 2017, told Brazil's UOL Esporte.

"[Button] has experience and I think we are very good at working together in terms of helping Honda, especially on the power unit side with the experience Jenson had with Mercedes in 2014 and myself with Ferrari."

"So I think we both have a lot of input to give."

Alonso and Button have so far gathered 18 and 13 points respectively.