I will leave the BBC later this year with a mixture of sadness and great affection

Sir Christopher Bland

Prime Minister Tony Blair and Culture Secretary Chris Smith have also said that they are pleased Sir Christopher is able to stay on for a few months.

Sir Christopher said there would be no conflict of interest between the two roles.

"The BBC editorial independence is sacrosanct," he said.

Peter Mandelson, the Hartlepool MP and former Labour Party communications director, said he did not think there was any problem in holding bost posts at the same time.

"BBC journalists have clear editorial guidelines to work within, regardless of who the governors are," he said.

But Liberal Democrat spokesman Norman Baker argued that Sir Christopher could not hold both posts simultaneously because there was a "clear conflict of interest".

He said: "Sir Christopher Bland can't possibly do two jobs at once.

"It confirms the view that the BBC's board of governors is past its sell-by-date."

Mr Baker said Sir Christopher had to resign as chaiman of the BBC board.

Sir Christopher said his five years as chairman of the BBC had been "a great privilege".

'Strength to strength'

He told the BBC's Breakfast News: "The BBC can be exhilarating and it can be obnoxious. But it is always wonderful and the BBC makes great, great programmes on television and radio.

"I have met and worked with hundreds of talented BBC people over that time who have made wonderful programmes and content for television, radio and online.

"I will leave the BBC later this year with a mixture of sadness and great affection."

Sir Christopher said the BBC and the board of governors had gone from strength to strength in the last five years.

He said: "Its funding is secure to 2006. It has ambitious and exciting plans for new digital services and a strong management team to deliver the strategy.

"My successor will find a highly creative organisation looking forward with optimism."

'Firm leadership'

Sir Christopher was appointed by John Major as chairman of the BBC in 1996 after a distinguished career in broadcasting.

He is a former chairman of London Weekend Television (LWT) and deputy chairman of the now obsolete Independent Broadcasting Authority (IBA), as well as a former director of ITN and GMTV.

BBC director general Greg Dyke said: "Christopher has been a strong champion and servant of the public interest and the BBC's independence in his stewardship over the last five years.

"I personally, and the BBC generally, are grateful for his firm leadership and wise counsel as chairman of the BBC Board of Governors."

Mr Dyke said it was good news that Sir Christopher would continue until a successor is appointed.

He added: "I wish Christopher well for his new challenge at BT."