Library workers in Greenwich are set to walk out for a second time next week after their employer failed to resolve a pay dispute.

More than 60 GLL workers are to stage another 24-hour strike on Tuesday, April 30 due as part of a long-running dispute over pay and the use of zero-hour contracts.

A previous strike in March saw more than 100 library workers from both Bromley and Greenwich walk out over pay.

Their employer, GLL, says it's a London Living Wage (LLW) employer, however, some employees reportedly receive below the LLW, which currently stands at £13.15 per hour.

GLL has also been accused by the trade union Unite of delaying the implementation of a rise to the London Living Wage by almost six months.

Unite says GLL workers are "furious" over the behaviour of their employer.

GLL has refused all offers from the trade union to come to the negotiating table.

In addition to the walkout, demonstrations are planned across the London on April 30, including at the British Library.

Unite general secretary Sharon Graham said: "GLL is behaving appallingly, and our members won't stand for it.

"There are an excess of injustices that come with zero hours contracts and a so-called social enterprise should be ashamed to use them.

"Our members are ready to fight for better pay and working conditions and Unite is right behind them."

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GLL defines itself as a staff-led organisation, however, only permanent employees get represented on their decision making board.

Of GLL's 10,800 workforce, 6,313 are on zero-hour contracts, which means most workers cannot stand for the board.

Unite regional officer Mary Summers said the GLL staff are being treated like "second class citizens".

She said: "Systematic failures to implement rises to the living wage show GLL is a substandard employer that is hiding behind its "social enterprise" status.

"Unite is standing with our members in tackling this shocking treatment."

A spokesperson for GLL libraries said that they are "disappointed and perplexed" by Unite's "continued campaign" against GLL, which they feel is "manufactured to reflect their national and political agendas".

They said: "This library strike does not reflect the opinion of the vast majority of our colleagues who are passionate about providing high quality library services. 

"All of our people benefited from at least a 5 per cent pay rise this April and we are an accredited Real Living Wage employer.

"We do not offer zero hours contracts, as erroneously suggested by Unite. 

"We do offer flexible working arrangements and give staff the opportunity to work with us in whatever way they choose.

They added: "Our commitment to staff and local communities in employment, career opportunities, fair pay, development and training is second to none and one of the reasons we are proud to hold Investors in People Gold accreditation.

"Our focus remains on ensuring that a quality library service continues to be delivered to local communities in Greenwich and that will be the case on April 30."