Laura Kuenssberg: Our exclusive behind-the-scenes access at No 10 as Andy Burnham became PM

Our exclusive behind-the-scenes access at No 10 as Andy Burnham became PM

"You can clap now," a Downing Street official with a clipboard instructed the staff eagerly lining the halls of No 10 in the moments before the new prime minister walked in.

The applause duly began before the famous door opened, so the first sight and sound to greet Andy Burnham and his wife were crowds of clapping staff, crammed into the Downing Street hall. They stretched up the long corridor all the way to the door of the Cabinet Room - left ajar for him to walk straight in and get down to work.

I've seen plenty of prime ministers come and go from outside No 10. But I'd never been allowed inside at that moment before, able to hover outside the Cabinet Room and grab a quick word with the country's new leader at such an intense, symbolic time.

I have rarely seen a politician look as thoroughly delighted as Burnham, pride bursting out of his buttoned-up suit - that's right, the T-shirt and bomber jacket didn't make it to No 10 - or a leader who has wanted to stop and shake as many hands.

What kind of prime minister will Andy Burnham be? In his first major broadcast interview since taking office, Laura Kuenssberg asks about his plans - and the challenges ahead.

No 10 staff are already wondering if they'll ever be able to stick to a regular prime minister's schedule, normally designed with military precision. If Andy Burnham was able to take the time to stop and speak to everyone in the country, I suspect he probably would.

It's a sign of his different style that our team was given permission to be behind the scenes at three key moments in the 59th prime minister's first week in charge - when he became Labour leader, when he walked into No 10, and on day one at his new Manchester outpost, No 10 North.

Most important by far was our half-hour interview in that shiny new office, after weeks during which Burnham was chased by accusations he'd avoided tough questions. But the extra glimpses we were given, alongside Burnham's own voracious appetite for social media, display a prime minister that's not just at ease in front of the cameras, but a leader who wants to bring you along for the ride.

They included revealing moments that are normally hidden - his first steps into the Cabinet Room to appoint his team, rating pub snacks with his Chancellor, John Healey, in an Instagram post, external, and sharing pictures with us of the family dog, Axel, whom he describes as having "angry little man energy".

"Comms" - how politicians communicate and explain themselves and talk to the publi