BRITAIN is facing a “low pay emergency,” striking workers from three separate disputes warned yesterday as they descended on bosses’ headquarters to demand a hearing.

Flying pickets mounted rowdy demonstrations across central London with striking hospital cleaners, British Airways and Bank of England staff rallying against poverty wages and pay freezes.

Outsourced cleaners and porters at four London hospitals are asking for a wage rise of 30p an hour, while support staff at the Bank of England are furious that pay has been frozen for the second year running.

Meanwhile British Airways cabin crew have walked out over pay differentials and victimisation.

On Thursday morning the workers joined forces to demonstrate outside City bank JP Morgan’s HQ where Serco, the contractor which Barts Health NHS Trust has outsourced its ancillary functions to, was holding a shareholders meeting.

The striking workers, represented by general union Unite, sang: “Serco, Serco, what you gonna do, what you gonna do when we come for you?”

Barts Health cleaner Eunice told the Star: “The money they’re paying us is too low. Before we were [employed directly by] the NHS, and now we’re private, and they said we were transferred on all the same terms and conditions. But now they’re making changes we’re not happy about.”

Unite organiser Willie Howard said: “We wanted to demonstrate that we can mobilise a huge amount of people not just industrially, but politically.”

Mr Howard said Serco had held out so far by “importing huge amounts of scab labour” but said the workforce was “prepared to keep striking.”

The workers were supported on the rally by activists from other unions including rail union RMT, which recently won the living wage for outsourced cleaners on Great Western Railway.

RMT executive member Jeff Slee told the rally: “As a result of a magnificent campaign, we were able to get a 40 per cent pay rise in one hit.

“You’re an inspiration to workers in your own industries, and also outside.”

The strikers then marched to the Civil Aviation Authority, which has given British Airways the thumbs-up to sub-let nine Qatar Airways’ aircraft — complete with scab staff — to cover for striking cabin crew.

Unite says this breaches regulations.

BA mixed fleet Unite rep Zimeon Jones said: “We’re going to focus on these big firms, focus on the Conservatives, until they meet our demands.”

The march then continued to the Bank of England — which has denied some ancillary staff a pay rise for the second year running.

This is in spite of the central bank’s governor Mark Carney telling trade unionists in 2014 that falling unemployment across Britain would lead to “sustainable pay rises that British workers deserve.”

Questioned about the strike yesterday, Mr Carney said it was “right that we have a limited budget relative to others in the public sector.”

The bank argues it focused its pay rises on workers who were paid less than they would be elsewhere.

On BA, today marks the 59th strike day by mixed fleet cabin crew. Bosses have withdrawn staff bonuses worth hundreds of pounds as well as axing travel concessions.

Since 2010 all new BA cabin crew have joined the “mixed fleet” rather than being divided into short-haul and long-haul workforces.

In spite of promises that pay would be 10 per cent above the market rate, Unite says mixed fleet cabin crew earn just £16,000 a year.

Unite national officer Oliver Richardson said: “In robbing striking workers of hard earned bonuses the airline has sought to sow division and effectively blacklist workers for taking lawful industrial action.”

Yesterday Unite said its BA mixed fleet members would strike for another fortnight.

A Serco spokesman said the company paid all Barts Health staff at least the London Living Wage, and had protected NHS terms and conditions.