Russian Prime Minister Mikhail Mishustin said Wednesday it was “impossible to give an exact date” for lifting of Covid-19 restrictions in Russia, including reopening the country’s borders.

In a meeting of the government’s coordinating council for combating the spread of coronavirus, Mishustin said:

It is still impossible to give an exact date when the restrictions imposed due to coronavirus can be completely removed, including at the borders of the Russian Federation.”

The Russian government previously barred entry to foreigners through April 30 to halt the spread of coronavirus, but Mishustin said he had signed a government decree extending border closings “until the fight against infection is complete and the epidemiological situation improves,” although he did not give further specifics.

Mishustin added that some exceptions would be granted to specialists who maintain specialized equipment needed for manufacturing essential items to fight coronavirus.