Employees at two McDonald's restaurants in England are set to strike over working conditions and the use of zero-hour contracts.
The action, if it takes place, would be the first strike at one of the fast food giant's restaurants on British soil.
The two restaurants involved are in Cambridge and Crayford, south-east London.
The Bakers, Food and Allied Workers Union (BFAWU) said staff were demanding a wage of at least £10 an hour and more secure working conditions, as well as the recognition of the right to form a trade union as employees of the company.
A BFAWU statement said: "Workers have found themselves living on low wages with no guarantee of hours. This has been viewed by some as punishment for joining a union, and has seen employees struggle to meet their rent payments, while some have even lost their homes."
McDonald's announced in April that workers would be offered the choice of flexible or fixed contracts with minimum guaranteed hours. The move was trialled in 23 restaurants and will be extended to 50 more sites before being rolled out nationally.
McDonald's, which employs around 85,000 staff in the UK, also promised that by May workers paid by the hour will have received an average hourly pay increase of 17% over the past two years.
A spokesman for McDonald's said: "We can confirm that, following a ballot process, the BFAWU have indicated that a small number of our employees, representing less than 0.01% of our workforce, are intending to strike in two of our restaurants.
"As per the terms of the ballot, the dispute is solely related to our internal grievance procedures. We are proud of our people at McDonald's. They are at the heart of all we do and we work hard to ensure that our teams are treated fairly. Our internal processes underpin that commitment."
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