Barely two weeks ago, the Westminster village was in uproar.

With the costs of government borrowing and inflation going up and grumbles from the business community about last October’s Budget growing louder by the day, Keir Starmer was asked if Rachel Reeves would still be chancellor come the next election.

The prime minister twice dodged the question, allowing journalists to speculate wildly about her long-term job prospects.

Fast forward to now and the contrast could hardly be more stark. Reeves is now driving the government’s agenda as Labour bets everything on growing the UK economy.

On Wednesday, the chancellor delivered a major speech setting out how she  hopes to achieve that, mainly by backing a wave of construction projects across the country, including a third runway at Heathrow Airport.

Given Starmer’s previous opposition to the expansion - and the cabinet splits which still exist on the issue - it suggested that Reeves is now calling the shots on Labour’s number one priority.

One Labour insider told HuffPost UK: “Rachel parked her tanks on everyone’s lawn with that speech.

“She’s effectively now the domestic PM and chief executive of UK Plc, with Keir the non-exec chair with a bit of foreign travel thrown in.”

But that was rejected by another senior party figure, who said: “Does that theory hold up in departments like health, education and the Home Office? There’s no sign of Rachel taking any serious interest in what is going on there, let alone Defra or DCMS.

“Just look at a small example like the Football Governance Bill. An interventionist domestic PM-style chancellor would be all over that, and the uproar from the Premier League, but she’s taken no interest at all.”

Sources in No.10 and at the Treasury both insist that Reeves and Starmer are “in lockstep”, something that has not always been the case with previous PMs and chancellors.

The Labour Party still bears the scars of the last time they were in government, when the bad blood between Tony Blair and his next door neighbour Gordon Brown often disrupted their attempts at running the country.

“Some of the nonsense about Rachel’s job being under pressure was absolute rubbish - Keir getting rid of her is never going to happen,” said one Starmer ally.

“They’ve got the closest relationship of any prime minister and chancellor since George Osborne and David Cameron. Rachel’s speech the other day was great, but No.10 and the Treasury worked on it very closely together.”

“Keir and Rachel do work together in a very complementary way,” said another source.

“In the past, a prime minister might have felt pretty insecure about a chancellor to be making such a wide-ranging speech setting out the government’s agenda for the rest of the parliament, but that wasn’t the case.”

But one Labour veteran sounded a note of caution, telling HuffPost UK: “Rachel and the Treasury have taken control of the domestic agenda and for the first time in the history of prime ministers it seems as though No.10 is very happy for them to do that.

“Whether that’s a sign of confidence or complacency is the question on everyone’s lips. And, of course, whether that close relationship lasts.”

Previously-anxious Labour MPs are pleased by the optimistic language now being used by Reeves and other members of the cabinet.

Where all the talk emanating from ministers was once focused on the £22 billion black hole and the terrible economic legacy bequeathed by the Tories, now they are striking a far more upbeat tone.

Business secretary Jonathan Reynolds raised some eyebrows earlier in the week by predicting that voters will start to feel better off this year, but that message has been welcomed by Labour MPs.

“For the first time they’re articulating vision in a way that ordinary people understand,” said one.

“They’ve learned the lessons from the Democrats’ defeat in America. There’s no point going on about economic growth unless you can show people that it will mean more money in their pockets.”

Another source said: “They seem to have finally realised that if you keep telling people the country’s in a mess they’ll start to believe it and just blame whoever’s in power. People like to hear a bit of positivity about the country’s prospects.”

Whether Labour is able to make good on its promises of better times ahead remains to be seen, but it is clear that Starmer and Reeves will be standing side by side come what may.

A Labour source said: “The past few weeks have been about the government seizing the agenda back on the economy after we cleared up the Tories’ mess.

“Westminster has got used to splits between No.10 and No.11 but that isn’t how Keir and Rachel work.

“They both know that we are only going to achieve what we want to achieve by working together and showing a united front on the economy.”