A judge in Fiji has ruled that US authorities can seize a Russian-owned superyacht worth $325m (£260m).
The Amadea had earlier been stopped from leaving the South Pacific nation because of its links to Russia.
A question remains over which of two Russian oligarchs really owns the luxury vessel, with only one of them facing sanctions.
Questions have also been raised about how far US jurisdiction extends into Fiji.
On Tuesday Suva High Court Justice Deepthi Amaratunga granted an order allowing the US to seize the superyacht after it had earlier filed a warrant.
But not straight away.
Defence lawyers have until Friday to put together their challenge.
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The judge will then decide whether to continue to put a hold on the yacht’s seizure pending a formal appeal by the defence.
According to Boat International, the Amadea is 106m-long and was built in 2017.
It features a stainless steel albatross that extends off the bow, a live lobster tank in the galley, a 10m (33ft) pool, a hand-painted Pleyel piano and a large helipad.
The US Justice Department in March announced the creation of a team of federal agents and prosecutors to pursue wealthy Russians or those aiding Russia’s invasion of Ukraine.
The team, called Task Force KleptoCapture, was set up to seize assets belonging to oligarchs with the aim of pressuring Russia to end the war.
The US claims the real owner of the Amadea is Suleiman Kerimov.
The economist and former Russian politician was sanctioned by the US in 2018 for alleged money laundering and has faced further sanctions from Canada, Europe, Britain and other nations after Russia invaded Ukraine.
Mr Kerimov made a fortune investing in Russian gold producer Polyus, with Forbes magazine putting his net worth at $14.5bn (£11.6bn).
But defence lawyers claim the real owner is Eduard Khudainatov, the former chairman and chief executive of Rosneft, the state-controlled Russian oil and gas company.
Mr Khudainatov currently does not appear to face any sanctions, unlike many oligarchs and people with close ties to Russian President Vladimir Putin, over the war in Ukraine.