The Kremlin said on Wednesday that Russia would defend its ships using the Baltic Sea with all means available and that a failed Estonian attempt to seize a tanker there recently showed that Moscow could respond with tough action if it had to.

On May 13, a mysterious ship named Jaguar sailed through waters near Estonia in the Baltic Sea. This ship, once registered under Gabon’s flag but now sailing without any national flag, was believed to be part of a “shadow fleet.

A Russian "shadow fleet" ship performed suspicious manoeuvres near the cable connecting Poland and Sweden, Poland's PM Donald Tusk said.