European Union members Lithuania, Latvia and Estonia have agreed to restrict the entry of Russian citizens travelling from Russia and Belarus, their foreign ministers said on Wednesday, published Reuters.

The three Baltic nations expect the entry ban to be in place by the middle of September, after it gets formal approval from the national governments, Latvian Foreign Minister Edgars Rinkevics said.

“In the last couple of weeks and months, the border crossing by Russian citizens holding Schengen visas have dramatically increased. This is becoming a public security issue, this is also an issue of a moral and political nature,” he told a press conference in Lithuania.

Finland, which also borders Russia, is not joining the ban due to legal uncertainty over whether it can refuse Russian nationals with Schengen visas issued by other European nations, Finnish Foreign Minister Pekka Haavisto told the briefing.

“Can you actually cancel the whole Schengen principles? This is, at the moment, still unclear,” he said.