BP is temporarily closing some of its UK service stations because of a shortage of truck drivers caused in part by Brexit.

“We are experiencing some fuel supply issues at some of our retail sites in the UK and unfortunately have therefore seen a handful of sites temporarily close due to a lack of both unleaded and diesel grades,” the company said in a statement shared with CNN Business on Thursday. BP (BP) blamed “industry-wide driver shortages across the [United Kingdom]” for the supply chain crunch. “We are prioritizing deliveries to motorway service areas, major trunk roads and sites with largest demand and seeking to minimize the duration of stock outs,” it added. BP declined to comment on how many gas stations would be affected, but a person familiar with the situation said that “tens” of sites were experiencing fuel shortages.

This is the second time in as many months that BP has had to temporarily shutter some UK locations because of problems distributing fuel due to a lack of truck drivers. According to the Road Haulage Association, the United Kingdom is short around 100,000 truck drivers, 20,000 of whom were EU nationals that left the country after Brexit. Esso owner ExxonMobil (XOM) said Friday that a “small number” of the 200 fuel stations it operates with supermarket chain Tesco (TSCDF) have also been affected. “We are working closely with all parties in our distribution network to optimize supplies and minimize any inconvenience to customers,” the company added in a statement.

Worker shortages are a growing problem in Britain, which had a record 1 million job vacancies between June and August, according to the Office for National Statistics. The UK government has announced some measures to increase the number of driving tests for truck drivers. But a spokesperson for the government said last month that “most of the solutions” will be driven by industry. “We want to see employers make long term investments in the UK domestic workforce instead of relying on labor from abroad and our Plan for Jobs is helping people across the country retrain, build new skills and get back into work,” the spokesperson said.