Yodel’s delivery drivers are voting on whether to go on strike in a move that could worsen the UK’s supply chain crisis.

The GMB union said it had opened a ballot on industrial action for more than 250 of its members on Wednesday, after failing to reach an agreement with Yodel over pay and working conditions affecting the delivery company’s lorry drivers.

The union said staff were angry over issues including a lack of work-life balance, and the fact that agency workers were paid more than drivers directly employed by the company. Workers are also concerned over a lack of payouts in lieu of annual leave and a failure to honour contractual agreements on pay for holiday and sick leave.

GMB added that workers were upset that Yodel had not offered any substantial pay increases that would keep drivers from leaving for better paying jobs elsewhere, especially at a time when employers across the country are scrambling to hire workers. “Yodel has seen fit to pick a fight with its loyal workforce in the midst of a chronic, nationwide driver shortage,” GMB union’s national secretary, Andy Prendergast, said.

A lack of lorry drivers, due in part to the Covid crisis and Brexit, has already put pressure on UK supply chains and left some retailers struggling to refresh their stock. Earlier this week, the Confederation of British Industry (CBI) said stock levels in August had fallen to their lowest level since retail industry trends were first tracked nearly four decades ago. That is partly due to worker shortages in several key industrial sectors, which have been compounded by a lack of foreign labour due to Brexit.

It has forced a number of companies to raise pay or bonuses in order to attract staff. Amazon has recently said it would offer joining bonuses worth up to GBP1,000 to help attract new workers, while other warehousing, transport and logistics companies including DHL and Whistl have announced similar plans.

The Yodel strike ballot will close in mid-September, which could mean industrial action also takes place during Yodel’s busiest season in the lead-up to Christmas. Yodel, which employs more than 10,000 staff, delivers more than 190 million parcels a year, according to the company’s website.

Prendergast said GMB has been trying to settle the dispute for months, but claimed “the Yodel top brass don’t want to listen”.

“Our members keep Yodel delivering parcels up and down the country. They know what they are worth and won’t back down until Yodel meet their reasonable demands,” he said. Yodel “should be moving heaven and earth to keep them on side”, Prendergast added.

Yodel said it was disappointed by GMB’s ballot plans and had been “proactive” in conversations with the union for a number of weeks. “We will continue to work with our union colleagues in good faith and are committed to further discussions to resolve any remaining matters” a Yodel spokesperson said.