David Alton, a crossbench peer and former Liberal Democrat MP, is warning his party has become 'narrow and intolerant' after Tim Farron resigned claiming it was 'impossible' to be a 'faithful Christian' and political leader.

In a damning indictment Lord Alton, an outspoken Catholic and former chief whip of the now defunct Liberal Party, said the Lib Dems have become a 'sect'.

He wrote on Facebook: 'In turning themselves into a secular version of the Exclusive Brethren they become a sect rather than a broad based political party. And they should reflect that millions of British people share his Christian beliefs.'

He added: 'It is ironic that a Party, which I joined as a teenager, because of its belief in conscience, human rights and free speech, has morphed into something so narrow and intolerant that, in resigning, its leader says "we are kidding ourselves if we think we yet live in a tolerant, liberal society" and has been forced to choose between his Faith and his Party.'

Tim Farron resigned on Wednesday night saying he felt 'torn between living as a faithful Christian and serving as a political leader'.

He told party activists: 'To be a political leader - especially of a progressive, liberal party in 2017 - and to live as a committed Christian, to hold faithfully to the Bible's teaching, has felt impossible for me.

'I'm a liberal to my finger tips, and that liberalism means that I am passionate about defending the rights and liberties of people who believe different things to me.'

He said he had been the 'subject of suspicion because of what I believe and who my faith is in', adding: 'We are kidding ourselves if we think we yet live in a tolerant, liberal society.'

His statement drew praise and concern from a number of church leaders including the Archbishop of Canterbury and raised questions over whether a socially conservative Christian will ever lead a political party again.

Lord Alton finished his rebuke by saying: 'This same narrow intolerance characteristic of the commentariat and the political elites has also fed into the creation of the less tolerant and unreasonable world in which we live.

'Tim Farron should never have been forced to make this choice but has made the right call and should be admired for doing so.'