Tanker freight rates have tripled since Russia invaded Ukraine two weeks ago, but most big operators aren’t hauling Russian oil and gas even though many governments haven’t halted imports of fuel from the country.

Daily freight rates for medium-size Aframax tankers, the crude-oil workhorses in the Black and Baltic seas, jumped to around $30,000 from roughly $10,000 before the invasion, freight brokers and tanker owners say. Such increases aren’t unusual during war.

A small number of tankers are continuing to serve Russian ports, and owners who are willing to take the risk of sailing into the Black Sea conflict zone can fetch more than $200,000 a day, the brokers and owners say. But most aren’t.

“Because of the complexity we will stay away from Russia,” said Lars Barstad, chief executive of Norway-based Frontline Management A/S, one of the world’s biggest tanker owners, operating 74 vessels. “There is a lot of money to be made, and it’s still legal, but very difficult to do in a good manner.”

At least a dozen tankers moving Russian crude have been temporarily seized or delayed at European ports by customs authorities over the past week, according to brokers and owners. Ship delays add to the cost of moving crude as vessels stay in the water for longer. 

The conflict in Ukraine has helped lift crude futures last month above $100 a barrel for the first time since 2014.

“They’ll hold your ship to see if it has any connection with blacklisted Russian companies,” said a tanker owner based in Greece, who had one of his vessels delayed in the U.K. “It’s not worth it.”

Russia is the world’s second-largest oil exporter behind Saudi Arabia. Dozens of tankers are operating daily at terminals like Novorossiysk, Russia’s largest port in the Black Sea, Taman Kavkaz at the Strait of Kerch and Primorsk, north of St. Petersburg in the Baltic Sea.

But ship traffic near Russian ports has fallen by around half, according to brokers. Maritime data provider Windward said the number of Russian-owned vessels that are on the market available to be chartered this week was triple that of Feb. 28.

The lower ship traffic comes amid an exodus of Western multinationals from Russia including major oil companies like Shell PLC and BP PLC. The U.S. on Tuesday barred Russian oil cargoes, while the European Union said it planned to cut oil-and-gas imports from Russia by two-thirds by the end of the year.

Oil giants charter hundreds of tankers from owners such as Frontline to move oil world-wide. Mr. Barstad said he expects tanker rates to stay strong or rise as oil importers have fewer options to buy crude and as the market adjusts to replace some 2.5 million barrels a day of Russian oil moved by sea.

The snubbing of Russian ports and ships has led to rising traffic and costs elsewhere in Europe. Ports in Cyprus, Bulgaria, Latvia and Finland are experiencing an increase in congestion of up to 80%, Windward says. In one case, international commodities trader Trafigura Group Pte. agreed to charter an Aframax tanker for $27,500 a day, 71% higher than a vessel of similar size it hired a month earlier, according to data from shipbroker Braemar. Trafigura declined to comment.

Not all carriers are opting against picking up Russian cargoes. China’s big state-owned operators like China Merchants Energy Shipping and Cosco Shipping Energy Transportation continue to move crude from Russia on their ships or on chartered tankers, people involved in the matter said. “Russian oil is still legal and someone has to move it to keep the market relatively steady,” a senior Cosco official said. “If other sources open up we will look at them.”

Tankers hauling Russian fuels are also finding alternate avenues to deliver products. Liquefied-natural-gas cargoes that were barred from entering the U.K. were unloaded in the Netherlands and Belgium, according to Kpler, a commodity-intelligence provider. The company said two supertankers that had loaded Russian crude via ship-to-ship transfers offshore Denmark were en route to Chinese ports and are scheduled to arrive in late March.

“Oil flows are like a river and when you cut one—the Russian oil—it will flow elsewhere to reach its destination,” Mr. Barstad said. “When a refiner is looking for a new source of oil there are inefficiencies in the movement, ships sail longer and this adds to the cost at the pump and brings more money to tanker owners.”

Tanker owners, looking to replace Russian crude, are waiting for governments to remove restrictions on ferrying product from Iran and Venezuela. But any deal with Iran, which produces around 2.4 million barrels of oil a day, will come as part of a new nuclear deal, now being negotiated between U.S. and Iranian officials. Venezuela, which is also under Western sanctions, used to produce around three million barrels a day, now pumps around 700,000 barrels a day, oil brokers and tanker owners said.

“You have to get your baseline energy needs from a reliable source,” Mr. Barstad said. “For Europe, Russia was the source, but it’s no longer reliable so you have a problem.”

Marex Media