Estonia warned on Thursday that Russia appears willing to defend with military force its shadow fleet of aging tankers dodging international sanctions to keep oil revenue and equipment flowing, even through the territorial waters of European countries.

Estonia has warned that Russia is willing to protect its shadow fleet of ageing tankers with military force. Moscow is thought to operate dozens of these oil-transporting vessels to avoid sanctions imposed on it after its full-scale invasion of Ukraine in February 2022.

Russia deployed a fighter jet in NATO airspace this week after Estonia tried to inspect a so-called shadow fleet tanker passing the EU-member’s economic area, Estonia’s Foreign Minister Margus Tsahkna said.