MOSCOW, May 22 (Reuters) - Russia's defence ministry has proposed a revision to the borders of Russian territorial waters in the Baltic Sea, according to a draft government decree, drawing a rebuke from NATO-member Finland.

According to the draft decree, dated May 21, the ministry proposed adjusting the border around Russian islands in the eastern part of the Gulf of Finland and around Kaliningrad.

"The passage of the state border of the Russian Federation at sea will change," a summary of the draft decree said. If approved, the decree would come into force in January 2025.

The defence ministry argued in justification of the change that an earlier Soviet measurement of the border from 1985 used mid-20th century nautical charts and so did not fully correspond to more modern cartographical coordinates.

It was not immediately clear from the draft decree exactly how the border would be adjusted and what - if any - consultation had taken place with other states around the Baltic Sea.

"The Finnish authorities are investigating information in the Russian media about the definition of maritime zones in the Gulf of Finland," Finnish President Alexander Stubb said.

"The government is monitoring the situation closely. Russia has not been in contact with Finland in the matter. Finland acts as always: calmly and based on facts."

Finnish Foreign Minister Elina Valtonen said that Russia should abide by the United Nations Convention on the Law of the Sea and said that Russia was sowing "confusion".