Poland has suspended sales of strong drinks from the Czech Republic where at least 20 people have already died of methanol poisoning, the country’s health authorities said on Sunday.

The Chief Health Inspectorate issued a one-month ban on the sale in Poland of all alcoholic drinks from the neighboring Czech Republic with the exception of wine and beer, the inspectorate’s spokesman said.

The Polish Health Ministry advised Polish nationals not to buy any drinks from the Czech Republic hit by the worst outbreak of alcohol-related poisoning in the last 30 years.

The Czech government also imposed a ban on all sales of liquor more than 20 percent alcohol despite heavy economic losses suffered by domestic spirits producers and sellers.