BBC director general Mark Thompson defended the corporation's coverage of Israel and Palestine.
He was speaking in advance of the corporation's official response to an independent report, commissioned by the board of governors earlier this month, which found "no deliberate or systematic bias" in the BBC's reporting of the conflict.
Thompson disagreed with the findings of the BBC board of governors'
report that a "guiding hand" should be appointed in newsrooms to reduce the potential for bias.
Speaking at the session entitled "Does Public Service Broadcasting Have a Future?", he described the BBC's approach as one of "critical realism" in which journalists use "sophisticated analysis" and "individual judgement"
balanced with a duty to get facts and provide an accurate view of the world.
He said the first principle of journalism provided by public service broadcasters was that it was impartial, dispassionate, disinterested journalism that was free from governmental or party political influence.
He said the suppression of independent sources was on the increase and mentioned Iran's recent move to block access to the BBC's Persian website from within the country.
Thompson said: "The site is not in any way anti-Iranian or anti-Muslim. It is simply seeking to make impartial and truthful news about Iran and the rest of the world available to those Iranians who want to access it."