Nestle has fired its chief executive after just one year in the job because he failed to disclose a “romantic relationship” with a “direct subordinate”.

The Swiss food giant, which makes Kit Kat chocolate bars and Nespresso coffee capsules, said Laurent Freixe has been dimissed with “immediate effect” following an investigation led by Nestle’s chair and lead independent director.

The BBC understands the inquiry was triggered by a report made through the company’s whistleblowing channel.

Nestle chair Paul Bulcke, said: “This was a necessary decision. Nestlé’s values and governance are strong foundations of our company. I thank Laurent for his years of service at Nestlé.”

The relationship was with an employee who is not on the executive board and the investigation began because it represented a conflict of interest, the BBC has learned.

Mr Freixe had been with Nestle for nearly 40 years but stepped up to the global chief executive role last September, replacing Mark Schneider.

Philipp Navratil has been appointed as Mr Freixe’s successor.

Mr Bulcke said the company was “not changing course on strategy and we will not lose pace on performance”.

Dan York-Smith, the former senior Treasury official Keir Starmer has appointed as his principal private secretary, is a qualified international gymnastics judge – a skill set that may come in handy as Labour limbers up for the formidable balancing act of Rachel Reeves’s autumn budget.

After a dizzying series of backflips on tax and spending, some of which were blamed squarely on the chancellor, the government is preparing to raise taxes – at the same time as acknowledging that with inflation on the rise again, the public are still in the grip of a cost of living crisis.

As well as York-Smith, who previously coordinated fiscal events at the Treasury and is well liked by colleagues across Whitehall, Starmer has pinched Reeves’s No 2, Darren Jones, to be his own “chief secretary” – a previously nonexistent job. The former Bank of England deputy governor Minouche Shafik, a well-respected economist, will be Starmer’s economic adviser.

Economists and former government advisers welcomed the reshuffle, suggesting it was high time for Starmer to take more interest in the direction of economic policy.

Jonathan Portes, a former senior government economist, said it was always a mistake to subcontract tax and spend entirely to the Treasury. “It is a well-functioning department staffed by people who know what they’re talking about and if it’s not politically challenged by No 10 things go wrong,” he said.

“Because of the way the Treasury works, it’s intellectually predisposed to do things that are not just politically counterproductive but economically counterproductive. You need somebody in No 10 to push back, and that’s in the interests of the government as a whole.”

Tim Leunig, the chief economist at Nesta, who advised Rishi Sunak when he was chancellor, agreed that part of the problem had been a lack of direction from No 10. However, he suggested any number of new appointments would make little difference without a clearer sense of what the prime minister wants.

“I think all this adds up to absolutely nothing, until Keir Starmer decides what he stands for, and what he stands against,” he said. In particular, Leunig said that would mean deciding which groups to single out to bear the brunt of tax rises – which are widely viewed as inevitable, with the Office for Budget Responsibility expected to downgrade its growth forecasts.

“Unless Labour are willing to say: ‘We’re never going to be a good government unless we’re lucky enough to get growth,’ then they’ve got to learn to pick some losers,” he said. Another former Labour adviser said these risks were particularly grave during tough economic times, when the Treasury tends to go into “finance ministry mode” – focusing above all on balancing the books.

However, Labour’s first year in power has underlined the political challenges of either cutting spending or raising revenue – particularly given the manifesto promises they made not to touch key taxes, including income tax.

Business groups have reacted with fury to Reeves’s £25bn increase in employer national insurance contributions, which has been blamed for putting the brakes on hiring and exacerbating inflation, while backbenchers forced the abandonment of £5bn-worth of disability benefit cuts. The removal of the winter fuel allowance from most pensioners was also almost completely reversed after months of damaging criticism.

Memories of previous disastrously received fiscal statements abound – including George Osborne’s “omnishambles” budget and, of course, Liz Truss’s “mini-budget”, much of which subsequently had to be ditched in the face of market chaos. With bond markets already skittish, the pitfalls are obvious.

As one Labour insider put it, the government’s task in the budget – which is still at least 10 weeks off, with no date yet announced – is to “fill a hole, in a way that makes it not look like they’re filling a hole”.

Reeves, meanwhile, has not yet found a replacement for her former chief economic adviser John Van Reenen, who has cut back his role at the Treasury – although she has roped in the pensions minister and wonks’ wonk Torsten Bell to be her wingman on budget prep.

Jones will be succeeded by the safe pair of hands James Murray, moving up from the post of exchequer secretary to the Treasury. Murray’s successor is another graduate of Bell’s former thinktank the Resolution Foundation – the MP for Chipping Barnet, Dan Tomlinson.

Shafik, too, had some involvement at Resolution, serving as one of the commissioners on its landmark Economy 2030 review – although she is better known as an expert on the international economy.

Margaret Thatcher famously used her economic adviser Alan Walters as an intellectual battering ram against the then chancellor, Nigel Lawson, ultimately leading to the latter’s resignation in 1989.

Few at Westminster expect Shafik to play such a divisive role, however. “She’s not like an Alan Walters figure: she’s not an ideological person,” one Labour insider said.

But given the political somersaults required, Portes argues that it will take serious political commitment from the very top of government to make another tax-raising budget stick. “No 10 and No 11 have to argue it out, agree, and then come out and sell it together,” he said. “And Starmer has to own it, not just Reeves.”