Russian airlines lease and operate roughly 515 foreign-owned planes, which are worth a total of around $10 billion. However, the EU ordered jet lessors to cancel all their contracts with Russian airlines by March 28—which, in practice, would mean lessors would need to get the planes back from Russian operators.

Lessors have been able to repossess these planes when they land in foreign airports, with about 78 seizures so far, according to Russian Transport Minister Vitaly Savelyev.

But lessors have few options to repossess planes within Russia, especially after Russian airlines like Aeroflot have halted almost all their international flights to protect their planes from seizure. ALI said that its members have had “limited success” in getting their planes back from Russia, potentially leading to billions of dollars in losses as Russian airlines appropriate their planes.

Ireland’s jet lessors have significant exposure to Russia. Ireland is a major hub for jet leasing, with ALI claiming that 60% of the world’s leased jets are owned by Ireland-based leasing companies. According to aviation consultancy IBA, Irish aircraft lessor AerCap—the world’s largest plane leasing company—has rented almost 7.5% of its portfolio, or about 145 planes, to Russian airlines.

However, investors seem optimistic about jet lessors’ ability to withstand the potential loss of their Russian planes. AerCap shares have recovered a little over half of their losses since Russia’s invasion of Ukraine. The company’s stock price is up 24% from its low point of $43.89 on March 7 but is still down 13% from its pre-invasion level of $63.

The loss of planes in Russia “is not going to cripple these businesses,” Brad Dailey, a director at Alton Aviation Consultancy told Reuters.

Unable to repossess their planes, lessors are now trying to recoup their losses from insurers. Earlier this month, after aircraft registries in Bermuda and Ireland suspended their certification of Russian-operated planes, Putin passed a ruling that permitted Russian airlines to re-register their planes in Russia. The law, in effect, would allow Russian airlines to commandeer foreign-owned planes and continue flying them domestically.

The new law spurred lessors to submit insurance claims, though legal battles over compensation are likely to take years.

Last week, Russia suggested it was willing to compensate foreign owners for planes appropriated by its airlines but the transport ministry said that lessors were currently uninterested in starting negotiations, perhaps due to the fact that any financial settlement might be seen as a sanctions violation.

But even if lessors eventually recover their planes, they still might not be able to recover all their losses. If Russian airlines continue to operate appropriated aircraft without the cooperation of foreign owners, jet lessors might lose access to up-to-date flight and maintenance records of their planes. Without access to those records, lessors may have to spend millions of dollars to reconstruct the plane’s records and conduct thorough safety checks.

It may be cheaper to write the plane off as a loss.