The loss of access to refueling points in the Mediterranean Sea poses major logistical problems for Russian oil tankers traveling from Baltic ports to Asia and also raises safety concerns due to possible entanglement at sea with flammable cargoes, say shipping sources. Russia is being swept away by a wave of severe financial sanctions on its banks, and oligarchs and foreign companies are severing ties after Moscow’s invasion of Ukraine, which Russian President Vladimir Putin calls a special military operation. Many factors led to the disruption of supply services, such as what sources described as “self-sanctions”, where companies try to stay ahead of the next wave of measures by refusing to contract with Russian entities. Payment problems due to banking restrictions have also burdened ship fuel agreements, which are usually priced and paid in US dollars. A source said Russian-flagged ships could not refuel ships in Malta, the British overseas territory of Gibraltar or neighboring Algeciras in Spain – all major refueling zones in the Mediterranean. “Several tankers had to make a longer voyage to refuel in other countries as European ports refused to supply fuel,” said another source familiar with one of the tanker’s movements. A Malta government official said the country would not allow any Russian-flagged ships to reach its ports. A spokesman for the Spanish Ministry of Merchant Shipping said it was “possible that some providers would adopt these measures independently”. A Gibraltar government spokesman said port authorities would “reject call requests from all ships, whether owned or operated by anyone connected with the country, or even for supplies, in accordance with UK rules. The spokesman said that as in Britain, foreign ships with Russian cargo would not be affected. Russia’s shipping industry is already struggling with the abolition of other services, including the certification of ships by leading foreign providers – vital to port access and insurance – retiring shipping companies and shipbuilders are suspending training in their equipment. Sources in the shipping industry say that given the complexity of world maritime trade, it was not clear how Russian companies could operate by withdrawing many services. The Danish marine fuel supplier and shipowner Monjasa said it had suspended “trade and supplies with Russian-flagged ships, Russian companies and individuals and individuals with ties or relations with Russian property” with effect from 25 February, one day after its launch. Russian invasion. Danish Bunker Holding said it had stopped all deliveries to Russian ports since early March, adding that the group and its subsidiaries, including Dan-Bunkering, had also “stopped making new commitments with Russian counterparties”. “We are aware of the challenges posed by this decision to suspend trade with Russian counterparties to customers and counterparties in the rest of the world, but with the dire situation in Ukraine we must act swiftly and decisively against Russia,” Bunker Holding said in a statement. Gibraltar bunker supplier Peninsula, which operates elsewhere in the Mediterranean and elsewhere, said in a post on LinkedIn that it “does not deal with Russian ships, ports, companies – owners or majority – suppliers and financial institutions.” Earlier this month, Britain announced sanctions on Russia’s largest shipping company, Sovcomflot. While the ban on Russian ships from EU ports is still under discussion, exporters of Russian oil and products have already faced problems chartering for ships and insurance, say shipping sources. Be smart with your money. Receive the latest investment information delivered directly to your inbox three times a week with the Globe Investor newsletter. Register today.