Civil service unions have hit back at Boris Johnson after he criticised a post-Covid “manana culture” that saw some staff prefer to work from home.

Relations between the Government and officials have been strained by a drive, led by Jacob Rees-Mogg, to get staff to return to their desks.

The Prime Minister said there was a “general issue” in the public sector – and perhaps more widely in the economy – about refusing to give up remote working.

Mark Serwotka, general secretary of the Public and Commercial Services union, told the PA news agency: “The level of offence that Boris Johnson is causing towards the hard-working people who kept this country running during the pandemic is astounding.

“PCS members worked flat out to deliver vital public services such as Universal Credit and the furlough payments, at a time when the Prime Minister was breaking his own rules by partying.

“It is nothing short of rank hypocrisy, and PCS members deserve better.”

In a TalkTV interview on Tuesday night, Mr Johnson acknowledged he had criticised a “post-Covid, work-from-home, manana culture” at some public bodies for not adapting after the easing of coronavirus restrictions.

As well as problems at the Passport Office, MPs have been raising concerns over significant delays in turning around applications for driving licences at the DVLA.

But Mr Serwotka said: “The high-profile delays that we have seen reported in passport applications and driving licences are down to his Government choosing to squander funds on dodgy PPE rather than invest in vital services.”

Mike Clancy, general secretary of the Prospect union, told PA: “The PM and his Cabinet must stop attacking hard-working and committed public servants who have no right of reply.

“Working from home existed before the pandemic and the Government should have a serious conversation with workers and unions on what truly flexible work looks like: not just for civil servants and office workers but for workers across the economy.

“Many of the problems that our public services face are thanks to over a decade of damaging spending cuts by the Government, not because of the attitude of public servants who are asked to pick up the pieces of this failed policy.”

Dave Penman, general secretary of the FDA union, said home-working had become the “go to excuse” for ministers.

“The passport delays have nothing to do with working from home,” he said. “It’s a surge in demand and a tight labour market.”

Government efficiency minister Mr Rees-Mogg is leading efforts to get staff back in Whitehall offices, challenging Cabinet colleagues to do more to encourage their officials to return to London.

The approach – which has seen him leave notes on vacant desks and threaten to remove the London weighting from salaries of remote workers – was criticised as “Dickensian” by Cabinet colleague Nadine Dorries.

Mr Johnson admitted using the words “post-Covid manana culture” during Tuesday’s Cabinet meeting.

He told TalkTv: “I think we have a general issue in some of our approaches to public services, and perhaps more widely, that we all got used to working from home, to Zoom calls, to thinking that we could do business like that.

“I think for many people it is great, I don’t want to minimise the value of this, I think for lots of people, particularly for women who have kids, for parents who have kids, I don’t want to be stereotypical, anybody who wants to stay at home for one reason or another, you can see the advantages of working from home.

“But I have to ask myself, I’m the custodian of the public purse and I’m looking at how much we’re taking and how much we’re spending, whether actually it is as productive.

“When I see institutions not delivering things like passports or driving licences in a speedy way, these things are quite expensive, it’s £150 to get a new passport, we want action.”