Russia’s challenges getting its oil exported stretched into a sixth day as tanker companies continue to fret that their ships could get ensnared if Moscow were to be hit with fresh sanctions following the country’s invasion of Ukraine.

Shipbrokers reported that a large number of owners remain reluctant to offer up their ships to transport Russian cargoes because they’re unsure there won’t be further action against the country for its attack.

If it continues, the difficulty convincing owners to go to Russia won’t just be a challenge for Moscow, but also for consumer countries that rely on the nation’s supply. Some local refineries are already turning elsewhere for crude. Russia uses tankers for almost two-thirds of its exports, earning about $100 billion a year in revenue at current headline oil prices.

The tanker companies’ wariness is in evidence in cargo loading lists from the country’s main western ports. Russia, and the companies that take its crude, need to find more than 80 tankers to collect about 61 million barrels of crude from the facilities this month. So far, a schedule of planned loadings shows just six vessels have been assigned for cargo collection. This time a month ago, there were 25 vessels listed for February cargoes.

In part, the emptier list is because the bulk of crude cargoes for March have yet to find buyers. Meanwhile, large numbers of oil tanker owners remain unwilling to let their ships collect Russian barrels while sanctions imposed on Russia in response to the invasion keep being adjusted.

It’s too early still to observe any notable change in export rates from Russia’s western terminals following the invasion, according to tanker tracking data compiled by Bloomberg.

There was already a backlog of ships at Novorossiysk in the Black Sea because of bad weather, meaning there were vessels in situ and waiting when the invasion began.

Freight, Insurance

However, if the difficulty organizing shipping persists, then that could start to affect cargo loadings later this month, according to traders.

This, combined with surging freight rates and insurance costs, means those companies that are willing to buy Russian cargoes simply can’t find suitable tankers at the right price.

Vessel owners, oil companies and marine insurers became instantly cautious of being involved in Russian crude shipments after the country invaded Ukraine on Thursday, wary of what the sanctions backlash might be. That caused the price of the nation’s flagship Urals grade to plunge to a record discount.

There are no sanctions at this time that would directly significantly impede international oil companies or shipowners from collecting Russian crude, and some traders have already overcome their initial wariness about doing so. But there is still uncertainty among several oil traders - and tanker companies—about dealing with the country’s barrels.