In a surprising about-turn, a UK court has granted insurers permission to appeal a landmark London High Court ruling requiring them to pay aircraft lessors more than USD1 billion under war risks insurance policies for jets stranded in Russia amid the Ukraine war.

This is according to Reuters, which reports that a hearing of up to five days is now expected to follow the March 31 decision.

In a previous judgment on October 6, 2025, Judge Christopher John Butcher of the Commercial High Court, Business and Property Court of England and Wales, had firmly shut the door on further litigation following two days of hearing arguments in September 2025.

The insurers had put forward dozens of grounds for appeal, but the judge, citing recent Court of Appeal guidance, reminded the parties that a trial "is not a dress rehearsal" but the "first and last night of the show".

He found that the insurers’ challenges to his findings on whether the aircraft were "permanently deprived" from their owners – and thus a total loss – stood "no realistic prospect of success". He emphasised the need for finality in the market, particularly with further related trials on the horizon.

In June, Judge Butcher had found that six lessors could recover losses under war risks cover for aircraft, and in some cases engines, leased to Russian airlines or airlines which operated in Russia.

The scale of the legal battle was laid bare in the figures for legal costs. AerCap's total costs were revealed to be GBP81 million pounds (USD108 million) – a figure insurers described as "astronomical". Judge Butcher ordered that insurers must pay 65% of AerCap’s costs.

The affected insurers and reinsurers who are defendants in the case are AIG Europe, Lloyd's Insurance Company, Chubb European Group, and the underwriting members of Kiln Syndicate 510 for the 2010 year of accounts, and others.

The complainants are AerCap, Dubai Aerospace Enterprise (DAE Capital), Falcon 2019-1 Aircraft 3 Limited, KDAC Aircraft Leasing, Merx Aviation Services, and GASL Ireland Leasing A-1 Limited.

By October 2025, DAE, Falcon, and Merx had settled with their insurers.