Last updated on .From the section Formula 1

The British Grand Prix is live on radio 5 live and the BBC Sport website

McLaren's Fernando Alonso will start the British Grand Prix from the back of the grid because of a total penalty of 30 grid places.

The Spaniard will have a new Honda engine fitted for Saturday practice, taking him even further over the limit in terms of total engine parts used this season.

In total, it adds up to 25 penalty places, in addition to the five-place penalty he already has for a new battery.

Honda has yet to announce the change but insiders have confirmed it to BBC Sport.

Drivers are allowed to use only a maximum of four of the six constituent parts of an engine all season.

Alonso's new engine will comprise his eighth turbocharger and MGU-H, the motor that recovers energy from the turbo, and his sixth internal combustion engine and MGU-K.

This is an addition to a new energy store - his fifth - that was fitted for Friday practice.

The number of grid places lost through penalties of all the engine suppliers in F1 this season so far. Going alright for Mercedes, Ferrari and Renault...

The new engine is one of Honda's 'Phase Three' fastest development ICEs, which give a power boost of a reputed 8kw (10bhp) over the Phase Two. That puts them just over 62kw (83bhp) down on a customer Mercedes engine.

The new parts are Honda's attempt to put an extra engine into their pool on a weekend when they were already going to get a penalty, thus limiting the damage to their competitive hopes.

McLaren and Honda want to be in the best possible position for the next race in Hungary, which is one of three this season when they expect to be most competitive along with Monaco and Singapore because of the lower impact the engine has on lap time.

The ongoing reliability and performance problems are continuing to put strain on McLaren's relationship with Honda.

Insiders say the team would like to split with the Japanese company and use Mercedes customer engines next year and are taking steps behind the scenes to make that happen but the situation remains in flux.

McLaren chief operating officer Jonathan Neale said: "We have a contract with Honda and we are working through some of the challenges we face.

"I can't duck the issue that we are not where we need to be and this season is challenging and frustrating.

"There is still a long way to go from where Honda are to the benchmark.

"F1 is where the best come to compete and competition is tough and unforgiving.

"I don't think it's something we can sit on lightly, so we are having those conversations.

"It's best they happen behind closed doors. We are working through our issues with Honda. We need to get it fixed and it is not sustainable in its current form."