Laura Kuenssberg: Keir Starmer takes the reins after impotence of opposition

Sir Keir Starmer formally became prime minister at lunchtime on Friday .

Whitehall has been quietly preparing for his arrival in Downing Street .

Treasury has apparently boxed in the urinal that has long been a feature of the chancellor’s private bathroom.

New ministers are likely to do everything they can to talk up how they want to get the economy to grow.

Labour mantra in public and private has been not just to win, but to be ready to get things done.

In their mind are what they see as the lessons of New Labour and Tony Blair's frustration with the slow pace of change.

One new minister tells of a meeting where they briefed the former PM about their plans and he warned them: “I so deeply regret that we didn’t hit the ground running on reform".

Sir Keir is not a factional politician who’s been in the trade, man and boy, not a product of student union elections, decades of party conferences.

For his backers, that arguable absence of an ideology is his huge advantage.

But despite the size of the majority, there is little sign at this moment that he could achieve that kind of personal popularity.