Ariane Sherine, the creator of the controversial Atheist Bus Campaign, will give the first atheist "Thought for the Afternoon" on BBC Radio 4 tomorrow.
The British Humanist Association hopes tomorrow's message, which will be delivered by television comedy writer Sherine on Eddie Mair's iPM programme, will pave the way for a non-religious "Thought for the Day" on Radio 4's flagship news show Today .
Sherine first came up with the idea for the atheist bus adverts, which proclaim "There is probably no God. Now stop worrying and enjoy your life", on the Guardian's Comment is Free pages last year.
Her campaign idea later received the backing of the BHA and has prompted almost 150 complaints from the public since it launched on public transport at the beginning of this week.
Andrew Copson, director of public affairs at the BHA, said: "Reflective thoughts on the events of the day do not come only from people with 'a faith' so it is wrong for the BBC – which has obligations to its many humanist listeners just as to its religious ones – to exclude non-religious contributors from Thought for the Day.
"The slot could only be enhanced by the inclusion of perspectives from the rich tradition of humanist thought and reflection."
Sherine added: "I'm really pleased and excited to be asked to give the first humanist 'Thought for the Afternoon'. I hope this is just the first of many from different humanist speakers, and that the Today programme will let humanists on very soon."
BHA member Gavin Orland set up a Facebook page last month to press the BBC to open Thought for the Day to humanist contributors.
But BBC Radio 4 controller Mark Damazer has so far resisted the calls to change. He admitted it was a "genuinely difficult question" but said the slot was intended to offer a "brief, uninterrupted interlude of spiritual reflection".
"I regard this as a genuinely difficult question. There may be a case for widening the pool of contributors on Thought for The Day by having someone with an avowedly non-religious perspective. However, on balance the BBC's position is that it is reasonable to sustain the slot with believers. Let me now set out the reasoning," he wrote on a BBC blog last week.
"Thought for the Day is a unique slot in which speakers from a wide range of religious faiths reflect on an issue of the day from their faith perspective. In the midst of the three-hour Today programme devoted to overwhelmingly secular concerns – national and international news and features, searching interviews etc – the slot offers a brief, uninterrupted interlude of spiritual reflection. We believe that broadening the brief would detract from the distinctiveness of the slot.
"Within Thought for the Day a careful balance is maintained of voices from different Christian denominations and other religions with significant membership in the UK. We are broadcasting to the general Radio 4 audience which regularly engages with the comments and ideas expressed by our contributors from the world's major faiths – whether they are believers or not."
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