A maritime chokepoint off the coast of Denmark that’s critical for the global oil market has become caught up in the European Union’s sanctions targeting Russia’s revenues from petroleum sales.

In June, the EU announced a ban on providing services and insurance for shipments of Russian oil cargoes anywhere in the world, as well as an embargo on most imports into the bloc. The measures are due to come into force in December for crude and next year for fuels. 

Once the restrictions kick in, shipowners will no longer be allowed to hire specialist pilots from EU companies to guide ships through the Danish straits -- part of limits on providing technical assistance, according to people familiar with the scope of the sanctions.

The restrictions on services could be loosened as part of discussions between the EU and the Group of Seven to introduce a cap on the price of Russian oil, which would allow shipments sold below an agreed threshold to access necessary services. 

The straits are unavoidable for shipments of crude oil and fuel from Russia’s Baltic Sea ports. Almost 2 billion barrels passed through them to reach global markets over the past two years, according to data compiled by Bloomberg.

The website of the Danish Maritime Authority states that in internal and external territorial waters there is an obligation for ships to use a pilot if they are carrying oil.

However, the waters used by international tankers are subject to the 1857 Copenhagen Convention that assures freedom of passage. As such, authorities can only recommend the use of pilots -- they can’t insist on hiring them.

That means owners could in theory send their ships through what can be a perilous stretch of water pilot-free. Two Danish shipping official said straits can be rocky, shallow and narrow in places, and subject to strong and surprising currents as well as bad weather. They can also be busy with merchant vessels.

DanPilot, the country’s main provider of pilots, refered inquiries to the Danish Maritime Authority. The DMA said in a statement that Denmark strongly recommends the use of pilots but that there’s no obligation on owners to use them.

Any vessels that do choose to transit without pilots might also end up doing so with inadequate insurance -- a painful choice for the industry and governments alike. The EU is to bar companies in its member states from covering Russian cargoes. 

That will blow a hole in cover provided by member organizations of the International Group of P&I Clubs and their reinsurers, given how many are either EU domiciled or affected by the bloc’s laws.

Should the US-led plan for a cap work, then both pilots and insurance would be available for owners -- provided they didn’t pay more than the price stipulated by the G-7.

The two Danish shipping officials both said they thought it was likely that the rules will ultimately be tweaked to allow pilots to guide ships through the straits for safety reasons.