A contractor has denied claims it used agency workers to cover a strike staged by parking wardens in Kingston.

GMB Union said it has lodged a complaint over the alleged use of agency workers by APCOA Parking during strike action in Kingston, which has so far seen wardens walk out for 17 days since November.

Using agency workers to cover striking employees is illegal. APCOA strongly denies the claim and said it has only used agency workers during the strike to fill pre-existing vacancies, which is lawful.

Kingston Council, which contracts its parking enforcement to APCOA, said it has been reassured by the firm that no agency workers have been used to replace striking wardens. The authority said it is content agency workers have only covered pre-existing vacancies and that this is supported by staff deployment data for strike days.

The parking wardens, who are all members of GMB, most recently walked out on Wednesday (July 30) as part of an ongoing dispute with APCOA over pay. GMB said the starting rate for wardens in Kingston is £13.85 an hour, compared to colleagues in Lambeth who recently secured an hourly rate of £15.

GMB said it has met with APCOA bosses for several rounds of talks but no formal pay offer has been made, despite repeated requests and rising frustration among workers. It told the Local Democracy Reporting Service (LDRS) it has also submitted a complaint to the Employment Agency Standards Inspectorate (EAS) over the alleged use of agency workers to cover the strike, which is investigating the claim.

The union urged the council to step in to help resolve the dispute. It warned strike action will escalate if no formal pay offer is made.

Alex Etches, GMB regional organiser, said: "Let's be clear: Kingston Council is short-changing and disrespecting the very workers who keep the borough running. They're happy to bank the millions in revenue these officers bring in but when it comes to fair pay, they look the other way.

"Other councils have stepped up, but Kingston has done nothing. GMB members have been left struggling to keep up with rising costs and it's just not good enough. This is a council-funded contract, and Kingston cannot hide behind APCOA."

An APCOA Parking spokesperson told the LDRS: "We are aware of recent allegations suggesting that we have used agency workers to cover for colleagues participating in industrial action. We categorically refute this claim. In line with UK law, we have not used agency staff to cover for striking workers. Any agency workers engaged during this period have been used solely to fill existing vacancies, which is entirely lawful.

"We respect the right of our colleagues to take industrial action and acknowledge their concerns. The current dispute relates to pay. We pay these colleagues the London Living Wage – a voluntary benchmark set by the Living Wage Foundation, which exceeds the statutory minimum wage.

"We remain committed to fair pay and to open, constructive dialogue with the GMB and their members."

A Kingston Council spokesperson added: "Kingston Council is proud of being an early adopter of the London Living Wage and that this commitment now extends beyond directly employed staff to those employed by private firms delivering services on the council's behalf.

"This commitment already includes APCOA's staff. The London Living Wage is independently calculated, is reviewed every year and rose by 5.3 per cent this year to reflect the higher costs of living and working in London.

"As the council is not the direct employer of the civil enforcement officers it has no formal role in the industrial action or any discussions which seek to resolve the dispute. We have consistently encouraged APCOA, their officers and their representatives to work collaboratively to resolve the dispute and ensure a return to normal service delivery in support of our residents."