Russia said on Wednesday that all vessels, including Russian ones, had free passage through the Baltic Sea and said that any attempt to violate international law on the free movement of shipping was dangerous.

Denmark will be tasked with inspecting and potentially blocking tankers carrying Russian oil through its waters under new European Union plans, the Financial Times reported on Wednesday, citing three unidentified sources.

“I’ll just remind you… that all vessels, including Russian ones, have the right to free passage through the Baltic Straits,” Maria Zakharova, a spokeswoman for the Russian foreign ministry, told reporters.

“Any actions that contradict this violate international law,” she said. “And you know how dangerous that is.”

Source: Reuters reporting by Dmitry Antonov written by Felix Light and edited by Guy Faulconbridge