Russians should stop coming to Crimea during the coronavirus pandemic, its Moscow-backed leader said Monday after a surge in traffic to the annexed peninsula this weekend.

Crimea, which Russia seized from Ukraine in 2014, banned all hotels and guest houses from hosting tourists without negative Covid-19 test results until June 1. Still, regional authorities noted a nearly 40% uptick in Friday’s vehicle traffic into Crimea from Russia.

“I never thought that I’d make this plea to fellow citizens, but there’s no other way: I strongly ask all our citizens to refrain from coming to Crimea, both for business and leisure,” Crimean leader Sergei Aksyonov said.

“All Crimean sanatoriums and vacation spots are closed,” Aksyonov said in a video address posted on his social media accounts.