BBC Radio 4's flagship Today programme was disrupted this morning as thousands of journalists staged a strike in protest at compulsory redundancies.
The BBC today refused to rule out compulsory redundancies in the face of "significant" Government cuts, despite a second strike by thousands of journalists protesting at job losses.
Members of the National Union of Journalists (NUJ) took industrial action across the UK, disrupting radio and TV programmes, including Radio 4's flagship Today, which was broadcast an hour later than usual.
Picket lines were mounted outside studios and offices, including the BBC TV Centre in west London, Bush House in central London and cities including Belfast, Glasgow and Manchester.
NUJ members will start a work to rule tomorrow, including a ban on overtime, which the union said would hit BBC programmes ahead of a meeting between the two sides on August 11.
NUJ general secretary Michelle Stanistreet told strikers outside Bush House in London: "We have had messages of support from other unions and members of the public who see that quality journalism is under attack."
She said journalists were angered at a "change in approach" by the BBC to job cuts, with a number of compulsory redundancies already made and more expected in the coming weeks.
The union posted photographs on its website of journalists on picket lines, while newsrooms were empty and programmes, including BBC2's Newsnight, were replaced.
Lucy Adams, the BBC's director of business operations, said in a message to staff that six out of seven employees were working normally and only "limited" changes to programmes had been made.
"We will continue to speak to the NUJ daily in an attempt to resolve the ongoing issues. However it is simply not realistic for us to agree to a policy of no compulsory redundancies when we face such significant cuts to the central Government grants that fund BBC Monitoring and the World Service.
"We will also carry on working to redeploy affected staff wherever possible. We have so far managed to redeploy 30% of staff at risk of compulsory redundancy in BBC Monitoring and 27% in the World Service. Nevertheless, we are clear we cannot create new jobs artificially nor can we give preferential treatment to NUJ members.
"We have repeated our apology to audiences today for any disruption they experience. Thank you to all of you who are continuing to work hard to deliver the high quality service that licence fee payers expect."