Mark Lawson, the presenter of BBC Radio 4's Front Row, is to leave the nightly arts programme after 16 years.

The broadcaster's departure follows allegations of bullying among several staff in the BBC Radio arts unit, which makes programmes including Front Row.

The claims of bullying are understood to have been made in a collective formal complaint by the National Union of Journalists.

Lawson, who also writes for the Guardian, is understood to have denied any suggestion of bullying, but acknowledges there were editorial arguments.

The broadcaster has been away from the programme for a month on medical grounds. He said he was taking a break from live radio journalism but hoped to return to Radio 4 at some point.

The 51-year-old, who is one of the BBC's most prominent arts broadcasters on radio as well as BBC2 and BBC4, said in a statement: "The BBC and I have agreed that I should step down as presenter of Front Row and for personal reasons I shall be taking a break from live daily radio journalism.

"It has been an extraordinary experience and privilege to work on the programme for 16 years and I very much hope to be able to return to work on Radio 4 in the future."

Lawson, who has written several plays for Radio 4 and four novels, has conducted about 3,000 interviews for Front Row and has been the programme's main presenter since it started in 1998.

Following his departure, the BBC said the programme, which airs on Radio 4 from Monday to Friday, would be presented by John Wilson and Kirsty Lang, alongside guest presenters such as Tom Sutcliffe.

The Radio 4 controller, Gwyneth Williams, said: "Mark has been an outstanding presenter of Front Row and we hope to work with him again in the future on Radio 4."

Asked about the allegations of bullying, a BBC spokesman said: "We don't confirm or comment on HR issues."

He added: "We can confirm that Mark Lawson is leaving Front Row. He has been away from the programme for a month on medical advice."

Twice voted TV critic of the year, Lawson wrote a column for the Independent before moving to the Guardian as a contracted writer.

A new series of the presenter's BBC4 interview show, Mark Lawson Talks To … is due to start next week.

Lawson presented The Late Show on BBC2 in the 1990s and The Late Review, which became the Newsnight Review and the Review Show, which moved from BBC2 to BBC4 last year.

Bullying at the BBC was a focus of a report by the barrister Dinah Rose QC published last year, which concluded that there were widespread allegations of bullying and an inadequate complaints procedure. The BBC arts unit complaints were unrelated to the Rose review.

On Front Row, which replaced Radio 4's arts programme Kaleidoscope, Lawson interviewed stars such as Dame Helen Mirren, Woody Allen and Russell Crowe, who stormed out of the Radio 4 studio after Lawson said he sounded a "little Irish" in his film portrayal of Robin Hood.