BALTIC naval powers are on high alert after Russia reportedly delivered on previous promises to start escorting so-called shadow tankers through the Gulf of Finland.

Following two separate Russian incursions into both Finnish and Estonian airspace in recent weeks in defence of shadow fleet tanker transits, Finland’s minister of defence Antti Häkkänen has confirmed that Russian naval vessels have also now been deployed to escort tankers.

Speaking to Finland’s national public broadcaster YLE, Häkkänen described the move as “unprecedented and aggressive”, echoing previous statements from Estonia’s defence ministry describing Russia’s recent behaviour in the Gulf of Finland as “dangerous and unacceptable”.

His comments followed confirmation from the Finnish ministry of defence on May 23 that two Russian military aircraft had violated Finnish airspace off Porvoo.

“There has always been a Russian military presence in the region. But what’s new in the current situation is that Russia is now escorting commercial tankers from its shadow fleet through the narrow waters of the Gulf of Finland. This involves warships and armed forces,” Häkkänen said.

The minister’s remarks came as two highly contentious tanker transits took place over the weekend with Russian, Finnish and Estonian naval forces all tracking progress from a distance even as both tankers spoofed their locations.

On May 25, an LPG tanker Falcon (IMO: 9014432) with no known flag and a history of AIS spoofing entered the Gulf of Finland signalling its destination as Tallinn. As with previous voyages, Falcon’s AIS signal indicated that it had anchored off Estonia, while the tanker was loading gas in Russia.

Falcon was removed from the Cameroon flag registry in August last year but continues to falsely broadcast its fits registration credentials.

Meanwhile, the previously flagless tanker Argent (IMO: 9293002), which triggered a Russian fighter jet response during Estonia’s attempted flag verification on May 13, exited the Gulf of Finland on May 26, but not before sparking another security incident.

Having been renamed as Blint and entered into the Comoros registry, according to its manually updated AIS signal data, the tanker departed from Primorsk loaded with Russian crude on May 25 only to spend five hours drifting near the Sweden-Estonia (EE-S 1) data cable.

Under the close monitoring of both Swedish and Estonian air patrols, Blint continued its journey signalling that it is awaiting orders.

While both tanker transits appear to have taken place without direct intervention from either Russian, Estonian or Finnish navies, the confirmation from Finland that Russia has now started deploying naval escorts will result in all future shadow transits becoming automatically considered politically contentious and high risk.

Following Blint’s most recent engagement with the Estonian navy, Russia’s UN Security Council representative Vasily Nebenzya labelled the actions of Baltic littoral states interrupting tankers transits to check documentation as akin to piracy.

A statement from the Kremlin meanwhile said that Russia was ready to use “all means” at its disposal in future to respond to such incidents.

Estonia, meanwhile, has vowed to continue verifying the insurance status of what it considers to be high-risk vessels transiting the Gulf of Finland.

“The Estonian Navy will continue fulfilling its tasks in accordance with international law as it has done previously,” Major Taavi Karotamm of the Estonian Defense Forces told Lloyd’s List.

“Ensuring protection of Estonian critical underwater infrastructure, and monitoring vessels passing Estonian Exclusive Economic Zone and territorial waters, together with validating the presented documentation of those vessels, are amongst the tasks of Estonian Navy. We will continue to assess each situation individually, and our response may vary accordingly.”

Russia and Estonia’s account of the incident involving Argent/Blint on May 13 differ significantly in that Estonia maintains that the navy did not make an attempt to board or detain the tanker.

Russia, however, claims that Estonian special forces made two botched attempts to board the tanker and when they failed an Estonian naval vessel rammed Argent/Blint.

Senior sources engaged with Nato security operations have told Lloyd’s List that an Estonian operation was underway but was aborted at the point that Russia scrambled a fighter jet in defence of the then flagless tanker.

Russia’s ministry of defence has made no further comments and has not confirmed Finland's assertion that naval vessels are being deployed to escort tankers.