MOSCOW - Russia has closed its airspace for planes from Latvia, Estonia, Lithuania and Slovenia, including transit flights, the country's Federal Agency for Air Transport announced Sunday.

"Due to the unfriendly decisions of the aviation authorities of Latvia, Lithuania, Slovenia and Estonia, restrictions are being introduced on air carriers of these states and/or those registered there to operate flights to destinations on the territory of Russia, including transit flights through the airspace of Russia," it said.

The four countries earlier introduced restrictions on Russian air carriers. Russia says its response is in line with international law, the agency said in a statement.

Some European countries, including Britain, Bulgaria, the Czech Republic and Poland, have also decided to close their airspace to Russia.