Pro-Brexit voices are being drowned out on the BBC’s news programming, an analysis has claimed.

Only a very small proportion of speakers on Radio 4’s Today programme are long-term supporters of leaving the EU, the Civitas think-tank said in a report.

The authors claimed the BBC has been unable to supply an example of a single programme since the June 2016 referendum which has examined the opportunities of Brexit.

Last night the BBC described the analysis as flawed and insisted it was ‘covering the process towards Brexit in a responsible and impartial way’.

The Civitas report, entitled The Brussels Broadcasting Corporation?, said that for the past 20 years the BBC has consistently viewed the issue of withdrawing from the EU through the prism of splits in the Conservative Party.

Only a very small proportion of speakers on Radio 4’s Today programme are long-term supporters of leaving the EU, the Civitas think-tank said in a report

Of 4,275 guests talking about the EU on Today between 2005 and 2015, only 132 (3.2 per cent) were supporters of leaving. And an analysis of four weeks of the programme in October and November last year found that it carried 97 interviews on EU topics, but only nine were with long-term supporters of Brexit.

Looking at Today’s business coverage in late 2016, Civitas found 53 per cent of speakers were anti-Brexit.

In the week of Article 50 being triggered last March, only 6.5 per cent of speakers in Today’s coverage were given space to be pro-Brexit, the report said. An analysis of a selection of Radio 4 programmes called the Brexit Collection found it included no attempts to explore the benefits of leaving, and only 23 per cent of contributors were pro-Brexit.

Civitas said pro-Brexit views have been under-represented on flagship BBC news programmes for decades.

In 274 hours of monitored BBC EU coverage between 2002 and 2017, only 14 speakers (0.2 per cent of the total) were Left-wing advocates for leaving the EU. These 14 contributors delivered 1,680 words, adding up to approximately 12 minutes.

In the same period two strongly pro-EU Tories, Ken Clarke and Michael Heseltine, made 28 appearances between them, with contributions totalling 11,208 words – over six times the amount of airtime allocated to all Left-wing Leave supporters.

The authors, David Keighley and Andrew Jubb, wrote: ‘When opinion in favour of leaving the EU has featured, the editorial approach has – at the expense of exploring withdrawal itself – tended heavily towards discrediting and denigrating opposition to the EU as xenophobic.

And an analysis of four weeks of the programme in October and November last year found that it carried 97 interviews on EU topics, but only nine were with long-term supporters of Brexit

‘The overview provided here is a shocking indictment of the BBC’s failure to achieve impartiality.’

They called for a judicial review to force the BBC to reform its complaints process.

The BBC said: ‘There have been a number of flawed “analyses” trying to depict the BBC as favouring one side or other. The reality is we’re no longer covering the binary choice of a referendum held 18 months ago, we’re covering the process towards Brexit in a responsible and impartial way independent of political pressure.’