The bards are setting their sights on the Cardiff-based station Radio Cymru - in particular the long-running Talwrn y Beirdd (Cockpit of the Bards) programme which challenges contestants to compose poems in strict metre.
The programme which goes out twice a week has a successful track record extending over 15 years and, the BBC says, it will continue with or without the critics. The bards complain that the station, a major player in Wales's cultural life, is abandoning the old values of strict grammar and pronunciation to make way for programmes aimed at younger audiences.
They insist that Radio Cymru, which now includes English rock and pop - and the occasional word in another language - must be an all-Welsh service, for the 500,000 fluent speakers among Wales' 2.6 million inhabitants.
One of the senior bards, Myrddin ap Dafydd, who owns a bookshop at Llanwrst in the Conwy Valley, said: "The BBC is undermining the reasons for the station's existence."
Geraint Talfan Davies, BBC controller in Wales and a fluent Welsh speaker, was unworried by the threat of industrial action. "This is clearly a special moment in industrial history. It needs to be commemorated in a special radio ode which we would be happy to commission."
The battle between purists and the populists was joined yesterday by Agenda, an independent company that supplies a nightly magazine programme to the Welsh Fourth TV Channel. Its editor, Rhodri Williams, ensures that popular Welsh personalities who cannot communicate in the language still get an airing. He said: "It is essential to have policies that include output for people who don't speak Welsh very well."Reuse content