Theresa May risked the anger of lowly-paid public sector workers by describing higher salaries as spending on “this, that and the other”.

The Prime Minister appeared to slip up during PMQs as she came under fire from Jeremy Corbyn over the harsh impact of the long-running cap on pay for state workers.

Ms May confirmed that a decision on whether to ease the cap would be taken later this year, when the annual “framework” is set out for the next financial year.

She then criticised the Labour leader, saying: “What he does in this House, and outside this House, is consistently stand up and ask for more money to be spent on this that and the other.

“He can do that in opposition because he knows he doesn’t have to pay for it. The problem with Labour is that they do it in government as well.”

The comment had echoes of the Prime Minister telling a nurse, in a pre-election TV programme, that there was “no magic money tree” to end her real-terms pay cuts.

It came as hundreds of nurses staged a noisy demonstration outside Parliament to end the pay cap. Several Labour MPs wore badges in support.

Meanwhile, civil servants are to be balloted for strikes in protest at their pay falling by between £2,000 and £3,500 in real terms between 2010 and 2016, it was announced.

In the first Prime Minister’s Questions since the summer break, Mr Corbyn went on the attack, saying: “The Prime Minister had no problems finding £1bn to please the DUP – no problems whatsoever.

“NHS staff are 14 per cent worse off than they were seven years ago. Are you really happy that NHS staff use food banks? Warm words don’t pay food bills – pay rises will help to do that. You must end the public sector pay cap.”

Ms May praised public sector workers, but insisted her Government would continue to “balance” higher pay with the need to invest in state services and to protect taxpayers.

Afterwards, her spokesman insisted she had not been describing public-sector pay as spending money on “this, that and the other”, but referring to other Labour spending commitments.

Earlier, the Prime Minister also ducked a challenge to condemn low pay in the private sector, after Mr Corbyn raised the current strike by McDonald’s workers.

He pointed out that company boss Steve Easterbrook is reported to have received £11.8m last year, while some of his staff are paid as little as £4.75 an hour.

The Labour leader urged Ms May to back the McDonald’s workers in their bid to end zero-hours contracts and secure “decent” pay.

But she replied: “The issue that is taking place in McDonald’s is a matter for McDonald’s to deal with.”

She added that the Government has taken action over zero-hours contracts, including banning exclusivity clauses – arguing there was only a “very small number” of such contracts.