Honda admit they "need to do everything" to improve their F1 performance as they bid to save their McLaren partnership.

The future of one of the sport's most famous team-engine relationships appears increasingly in jeopardy after McLaren executive Zak Brown delivered an unequivocal warning to the team's partners this week.

McLaren's philosophy stops working

Expressing disappointment that a planned upgrade for this weekend's Canadian GP had not materialised, Brown said Honda appeared "lost" with their F1 programme and that McLaren had "serious concerns" about the Japanese firm's ability to win a world championship, the partnership's stated aim since reuniting amid much fanfare in 2015.

Responding to Brown's comments and renewed speculation that they are heading for divorce, Honda's F1 chief Yusuke Hasegawa said he understood McLaren's frustrations and accepted big improvements needed to be made.

"It is very unfortunate we can't convince them that we can do that," he said. "From the results point of view, of course we need much improvement from the performance and reliability point of view.

"So we will do everything. We need to do everything."

Performance and reliability problems have plagued the first three years of Honda's F1 return, with a fresh wave of problems at the start of this year leaving eight-time constructors' champions McLaren without a point and at the foot of the Constructors' Championship.

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"Of course, we are talking together, even this morning, and it's obvious we are frustrated with the current situation and are disappointed with our team result," said Hasegawa.

"So there's no wonder there are some complaining comments. But the things we can do is trying our very best for the team and we are still aiming to go the same direction."

Although McLaren have never publicly confirmed pre-season reports they approached Mercedes about a 2018 engine deal, Brown told the BBC on Friday that "we have a plan B, we have a plan C" for next season and that they aim to make a decision on their engine for next season before the August summer break.

Fernando Alonso doesn’t finish FP1 after a loss of hydraulic pressure at the Canadian GP. Fernando Alonso doesn’t finish FP1 after a loss of hydraulic pressure at the Canadian GP.

Honda's attempts to convince McLaren they remain the right fit for their future ambitions appears likely to be made harder by a further wait for the company's engine upgrade.

Having already racked up grid penalties for unreliability this season, Hasegawa stressed the team's factory in Japan is "trying hard" to ready the new package but conceded he "can't promise" when it will be ready to race.

Can Mercedes hit back in the 2017 title fight with Ferrari? Don't miss the Canadian GP live only on Sky Sports F1 this weekend. The race starts at 7pm on Sunday. Watch the race for £6.99 on NOW TV

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