Image caption John Humphrys in the Today programme studio

Broadcaster John Humphrys is presenting his final edition of BBC Radio 4's Today programme.

His departure brings to a close his 32 years on the flagship show, during which time he built a reputation as a tenacious interrogator of politicians.

Thursday's programme will feature interviews with former prime ministers David Cameron and Tony Blair.

BBC director general Lord Hall said public figures would breathe "a sigh of relief" at Humphrys' departure.

Describing him as "a journalistic great", the director general wrote in The Daily Telegraph: "He is driven by a profound sense of justice and a deep distrust of authority. It means that he has always, unerringly, represented the listener and championed their right to know."

He added: "There is perhaps no greater tribute than the collective sigh of relief issued by leaders and public figures all over the country."

Humphrys has interviewed every prime minister on the programme from Margaret Thatcher to Theresa May, but has not grilled Boris Johnson since he came to power.

Today editor Sarah Sands joked that Mr Cameron, who is likely to be questioned about his decision to call the 2016 Brexit referendum, said he was coming on Thursday's programme "to make sure he got the old bugger out of the building".

"He doesn't let go," Sands said of Humphrys on Radio 4's The Media Show. "He's a terrier, so I think you should expect something exciting."

Media playback is unsupported on your device Media caption Humphrys announced his departure earlier this year

Yet Humphrys does more than just give politicians a tough time, she added. "John is rather caricatured in that way," she said. "He's capable of that style of interviewing [but] he's supple as well."

Mr Blair will take part in a discussion about political interviewing, and Today presenters past and present will pay tribute.

Today will continue with four main presenters - Justin Webb, Mishal Husain, Martha Kearney and Nick Robinson - and will not directly replace Humphrys. The 76-year-old will continue to present Mastermind on BBC Two.

Before joining Today in 1987, Humphrys worked as a BBC foreign correspondent in both the US and Africa, as a diplomatic correspondent and as a presenter of the Nine O'Clock News.

On the daily Radio 4 morning news programme, he became known for pinning down political leaders and public figures. On occasion, his interviewing style incurred the ire of both politicians and listeners.

Image caption Humphrys will stay behind the Mastermind host's desk

When he announced his departure in February, Humphrys said: "I love doing the programme. I have always enjoyed it. That's the problem. I should have gone years ago. Obviously I should have gone years ago."

He is Today's longest-serving presenter and has been one of the corporation's highest earners. His salary in 2016-17 was between £600,000-£649,999, but he took a pay cut and went down to £290,000-£294,999 in 2018-19.

In a tribute in the Radio Times, Justin Webb said: "There are plenty who don't like him, who think he's gone on too long, who want him 'pensioned off' or 'put out of his misery' or whatever the phrase is they use to suggest that being a man in his 70s on air is somehow an affront.

"Most of these folks would see themselves as impeccable anti-sexists and anti-racists, but ageism is alive and well and apparently deeply acceptable in the anti-John movement."

Image caption Humphrys after interviewing Tony Blair in 2005

Webb also told the magazine: "John doesn't give a stuff what you think of him. He is bemused when Jon Snow of Channel 4 News talks of his followers online. Why would John want followers?

"John wants enemies, or at least for respect, when it is paid, to be paid only grudgingly."

Speaking on Desert Island Discs in 2008, Humphrys said he did not think most politicians deliberately told lies on the programme.

But he said: "I do start with the assumption that they are there for their benefit, rather than necessarily for the benefit of the audience. And it's my job often to try to get them to be a bit more candid than perhaps they intended to be."

Image caption Humphrys with co-host Sue MacGregor in the Today production office in 1993

Six of Humphrys' most memorable (and controversial) interviews

He said his first interview with a prime minister - with Margaret Thatcher in 1987 - was "a truly scary prospect". But he showed his knack for getting insights into politicians' characters when he asked about the link between her Christian faith and her politics. "How can you express unselfish love if you have no choice?" she said. "The fundamental choice is the right to choose between good and evil."

in 1987 - was "a truly scary prospect". But he showed his knack for getting insights into politicians' characters when he asked about the link between her Christian faith and her politics. "How can you express unselfish love if you have no choice?" she said. "The fundamental choice is the right to choose between good and evil." Cabinet minister Jonathan Aitken accused Humphrys of "poisoning the well of democratic debate" in 1995 after saying he had interrupted then Chancellor Kenneth Clarke 32 times. But Humphrys got support from other ministers and the Daily Mail, which called him "one of the most brilliant journalists in the country". The next time Mr Clarke appeared on Today, Humphrys gave him a calculator to count how many times he was interrupted.

accused Humphrys of "poisoning the well of democratic debate" in 1995 after saying he had interrupted then Chancellor Kenneth Clarke 32 times. But Humphrys got support from other ministers and the Daily Mail, which called him "one of the most brilliant journalists in the country". The next time Mr Clarke appeared on Today, Humphrys gave him a calculator to count how many times he was interrupted. Labour director of communications Dave Hill spoke publicly of "the John Humphrys problem" after the presenter's robust confrontation with social security secretary Harriet Harman about plans to reduce payments to single mothers in 1997.

about plans to reduce payments to single mothers in 1997. An early morning three-minute interview with correspondent Andrew Gilligan in 2003 led to a confrontation between the BBC and the government. Gilligan said he had been told by a reliable source that a government dossier about the threat from Iraqi leader Saddam Hussein's weapons of mass destruction had been deliberately "sexed up". This ultimately led to the suicide of the source, Dr David Kelly, and the resignations of Gilligan, the BBC director general and the BBC chairman.

in 2003 led to a confrontation between the BBC and the government. Gilligan said he had been told by a reliable source that a government dossier about the threat from Iraqi leader Saddam Hussein's weapons of mass destruction had been deliberately "sexed up". This ultimately led to the suicide of the source, Dr David Kelly, and the resignations of Gilligan, the BBC director general and the BBC chairman. Humphrys hastened the downfall of another director general, George Entwistle , in 2012 with a interview about how Newsnight wrongly implicated a former Conservative deputy chairman in a child abuse scandal. Entwistle, who struggled badly and appeared out of his depth, resigned soon afterwards.

, in 2012 with a interview about how Newsnight wrongly implicated a former Conservative deputy chairman in a child abuse scandal. Entwistle, who struggled badly and appeared out of his depth, resigned soon afterwards. Humphrys got into hot water for a leaked off-air exchange about the BBC's gender pay gap with North America editor Jon Sopel in 2018. It followed the resignation of Carrie Gracie as BBC China editor over pay inequality. In what Humphrys described as a "jokey" exchange, he asked Sopel about "how much of your salary you are prepared to hand over to Carrie Gracie to keep her".

Follow us on Facebook, or on Twitter @BBCNewsEnts. If you have a story suggestion email entertainment.news@bbc.co.uk.