Gary Lineker ignites yet another impartiality row as he signs an open letter criticising the Rwanda scheme alongside a host of other celebrities

Gary Lineker has ignited another BBC impartiality row after he signed an open letter criticising the Government's Rwanda policy.

In a move that threatens to further embarrass his employers, the Match of the Day host has publicly endorsed calls for the policy to be scrapped.

Lineker's intervention prompted an outcry from politicians exasperated by his posturing, with one telling him: 'Put a sock in it.'

The pundit is among a host of celebrities who have put their names to the letter from campaigners Together With Refugees. It is designed to pressure MPs on the eve of a crunch parliamentary vote on the policy.

Actors Brian Cox, Juliet Stevenson and David Morrissey, as well as Kaiser Chiefs musician Simon Rix, are among more than 30 people to sign the letter. Others include Unison union boss Christina McAnea and leaders of several faith groups.

The letter describes Britain's refugee system as 'ever-more uncaring, chaotic and costly' and accuses the Government of 'trying to banish people fleeing persecution to Rwanda'.

Addressed directly to the country's 'political leaders', it says the Government's policies 'aren't working'. The highly political tone of Lineker's latest intervention is another brazen challenge to the authority of his BBC paymasters and potentially breaches its guidelines banning flagship presenters from taking up a role 'in campaigning groups'.

The letter states: 'Our government is still trying to banish people fleeing persecution to Rwanda despite the highest court in the land ruling the scheme unlawful.

'These policies aren't working for refugees and they aren't working for local communities. That's why we have come together to say we've had enough. Enough of the division. Enough of the short-term thinking. Enough of the wasted human potential. And it's why we now call for something better.'

Endorsing the activists' demands, Lineker, the BBC's highest-paid star, said: 'Refugees have escaped unthinkable horrors in their home countries.

'We need a new system that reflects the will of the British people.' The letter calls for the UK to uphold its commitments under international law, and demands the 'scrapping of the Rwanda scheme' and an overhaul of asylum policies.

Lineker's remarks provoked a furious reaction among Tory MPs, who called for BBC director-general Tim Davie to intervene.

Jonathan Gullis said: 'This is yet again another breach by Gary Lineker that goes against the BBC's impartiality rules. But, sadly, spineless Tim Davie will do nothing about it, having surrendered to him previously. Either the BBC enforces the rules its presenters are bound by, or they no longer receive funding from the British taxpayer.'

Tory party deputy chairman Lee Anderson said: 'For once in his life, Gary's absolutely right – we do need a system that reflects the will of the British people. What the people want is to stop the boats and to tell overpaid crisp salesmen to put a sock in it.

'Alongside cracking down on illegal migration, we need another robust system which keeps Lineker as far away from the public as possible, to give us all a rest from his Left-wing, out-of-touch nonsense.'

Dartford MP Gareth Johnson said: 'Yet again BBC presenters are ignoring the BBC's own guidelines by publicly campaigning. They seem to be laughing at their own bosses.' The backlash will cause a fresh headache for BBC bosses at the end of a year marred by repeated crises over Lineker's political crusading.

In March, the presenter was hauled off air after refusing to back down over a tweet comparing the Government's language on asylum seekers to 1930s Germany.

But the corporation was forced into a humiliating climbdown when staff walked out en masse in support of Lineker and he agreed a deal allowing him to tweet about refugees and climate change.

Signing an open letter in support of a political cause is not explicitly covered by the BBC's guidelines on impartiality, creating a grey area that could help Lineker.

But he could be seen to have broken other guidelines governing how 'flagship programme presenters' should conduct themselves publicly, which were drawn up to govern social media output. One section of the guidance says: 'Don't take up an official role in campaigning groups or become involved in fundraising for campaigning.'

Since the showdown in March, Lineker has shown little sign of tempering his political outbursts and even gloated that the corporation 'admitted they had got it wrong' when they took him off air.

He used an interview with former Labour spin doctor Alastair Campbell to repeat his claim that the 'language' in the debate over the Rwanda refugee policy 'reminds us of the debate in Germany in the 1930s', adding: 'I think that is factually accurate.'

Lineker, who earns £1.35 million a year from the BBC, also said that, after he was first suspended over his incendiary tweets, he found it 'hard to see how it got resolved unless they backed down'.

In May, he flew to Italy to receive an award for his 'woke' political activism from Amnesty International. At the time, he was accused of indulging in a 'self-congratulatory fest'. Days later, Lineker stoked more controversy by claiming the climate fanatics who had been causing chaos on London's roads may well be remembered as 'heroes'.

A BBC spokesman said last night: 'Like all freelance presenters, Gary is free to contribute to projects for third parties, as long as these do not conflict with his BBC commitments; do not breach guidelines on conflicts of interest; nor bring the BBC into disrepute, and he does so regularly.'