He added: ‘I share the commitment of the Labour government to improve public services but frankly I don’t think the language is always helpful when you try and paint those who are delivering public services often at the sharp end in difficult circumstances as somehow part of the problem.

‘Now the civil service public service workforce is like any workforce there are some people who don’t pull their weight.

‘To characterize the vast majority of people who are working hard day in day out as somehow the part of the problem and that’s what they do I think is unfair. ‘

Mr McFadden said it is not an ‘ideological approach to stripping back the state’, but said that the Government does want to get ‘bang for our buck’.

Asked how radical they are willing to be, Mr McFadden told the BBC’s Sunday with Laura Kuenssberg: ‘Performance management is part of every big organisation, but it’s an important thing for you and your viewers to remember: we’re a centre-left government.

‘We believe in good public provision, that’s why we fought the election, saying we wanted to have more teachers in schools, more neighbourhood police officers, why we wanted to get waiting lists down.

‘It is part of what we believe in that the state can provide both security and opportunity for people.

‘That will guide us in our actions, it’s up front in our policies, so we will be radical about this, but it’s about getting bang for our buck in terms of the outcomes for the public, it isn’t an ideological approach to stripping back the state.’

Last night, Government sources insisted the plans would save money in the long run by improving the quality of the Civil Service overall.

It comes three months after Sir Keir angered public sector trade unions for claiming too many Whitehall officials were ‘comfortable in the tepid bath of managed decline’.

Labour MPs were braced for a backlash, as one said: ‘Getting the best out of public servants is a good idea but you don’t do it by threatening them with the sack.’

Tory MPs also doubted Sir Keir’s commitment to take on the so-called public sector ‘Blob’, noting that just days after his ‘tepid bath’ attack in December the PM appeared to row back by issuing a gushing letter to civil servants praising their ‘dedication and professionalism’.

However, Mr McFadden, vowed to ‘stop the carousel of people being shuffled from job to job, with performance issues never being dealt with’.

The Prime Minister is set to unveil proposals to sack under-performing mandarins as well as link the pay of some top officials to specific work targets

This week’s moves are being billed as the latest steps in Labour’s ‘Plan For Change’ programme in a bid to reshape the British state.

And Mr McFadden will use a speech this week to say that while the number of people working in Whitehall departments had increased by 15,000 since 2023, people had yet to see improvements in job opportunities, the safety of their neighbourhoods or the length of time they have to wait for NHS treatment.

He will unveil plans to:

• Introduce private sector-style ‘Mutually Agreed Exits’, where civil servants without the skills and performance required will be incentivised to leave their jobs, instead of going through lengthy formal processes.
• Quickly weed out underperformance among the highest-paid civil servants, with those who do not meet the standards required to be put on a ‘Personal Development Plan’, with a view to dismissing them if they do not improve in six months. 
• Set out a new pay-by-results system, making sure the most senior officials responsible for the Government’s ‘Missions’ have their wages linked to the outcomes they achieve. 

Asked on Sunday with Laura Kuenssberg on the BBC where he broadly thought the number of jobs cuts should be, the Chancellor of the Duchy of Lancaster said: ‘I think the old tactic of picking a headcount number for reduction hasn’t worked.’

He suggested that former prime minister Boris Johnson said numbers would be cut, but they then increased.

Mr McFadden said: ‘I actually don’t think this should be the guiding principle. The guiding principle should be, how can the state change?’

Pushed again, Mr McFadden said: ‘I think the central civil service would and can become smaller.

‘I want to see more civil servants working outside London, where I think the state can get better value for money.’

He added: ‘We also want to see more data and digitally-skilled people in the civil service. Not enough at the moment. I’d like to double that proportion by the end of the decade.’

The general secretary of the FDA, a union for civil servants, has said that meaningful reform ‘must put substance before headlines’ and any announcement that ‘points the finger’ at public staff ‘only reinforces the sense that the Government lacks of a credible long-term plan’.

Dave Penman said: ‘If the Government is serious about transforming public services they must set out what the substance of reform looks like, not just the retreading of failed ideas and narratives.’

He added: ‘If the Chancellor of the Duchy of Lancaster wants civil servants to focus on delivery, while at the same time government departments are cutting resources, then ministers need to set realistic priorities.

‘Delivering more for less is a soundbite, not a credible plan for change.

‘Government should get on with the difficult job of setting those priorities rather than announcing a new performance management process for civil servants every other month.’