The sacking of the top Treasury official by Liz Truss’s Government has been condemned as “pretty disgraceful”, “retrograde and worrying” by a former head of the civil service.

Ex-Whitehall chief and independent crossbencher Lord Kerslake said Sir Tom Scholar’s dismissal marked a “problematic” shift towards ministers installing civil servants who agree with their views.

Chancellor Kwasi Kwarteng’s move to oust Sir Tom on the first day of the new administration sparked a backlash in Whitehall.

Ms Truss had previously railed against “Treasury orthodoxy”, with the sacking seen as a signal of her determination to change the direction of economic policy.

Lord Kerslake warned it would have a “chilling effect” on public confidence that ministers are receiving robust advice.

He told The Guardian: “What seems to have happened here is that they had a view about what they perceived was his approach to the policy side of things, and they decided they didn’t want to have that sort of robust advice on the issues.

“That is precisely what senior civil servants are there for. Even more than before, senior civil servants will be nervous about this and worry that robust advice is interpreted as political differences with their policies.

“It marks a new level of the growing trend of blaming the civil servants and dismissing them, and essentially saying they want a senior civil servant who aligns with our personal views.

“I think that is really problematic … I think there will be a chilling effect and the wider world will be less confident that decisions will be made on the basis of robust advice.”

The peer joined a growing chorus of anger over the sacking of Sir Tom, who worked in the civil service for three decades.

Lord Wilson, who headed the service under Tony Blair, said in a letter to The Times: “To summarily dismiss a key top official, judged by most people to be outstanding, at this moment is destabilising.

“It is contrary to established practice and is bound to create ripples as consequential moves take place.”

Lord Wilson also described as “ill-judged” an intervention by former Treasury minister Lord Agnew, who on Tuesday defended the sacking, branding Sir Tom as the embodiment of “the malign influence of the Treasury orthodoxy”.

The ousting was also criticised by former cabinet secretaries Lord Butler and Lord O’Donnell.