The 22-year-old Warmbier, who was detained in North Korea for allegedly removing a propaganda poster from his hotel, died days after being sent back to the United States in a coma in 2017.
His parents, Cynthia and Frederick Warmbier, sued North Korea for the alleged torture and murder of their son, with a US judge ordering Pyongyang to pay them $501 million in 2018.
Impoverished North Korea, struggling under biting international sanctions over its nuclear weapons programme, is believed to have few assets in the United States and has ignored the 2018 ruling.
Last week, Judge Lawrence Kahn of the Northern District Court of New York approved the seizure of the funds from North Korea’s Korea Kwangson Banking Corporation after they failed to respond to a forfeiture order.
“Judgement is hereby entered in favor of the Plantiffs/Judgement Creditors Cynthia Warmbier and Fredrerick Warmbier with respect to the Subject Funds in the sum of $240,336.41, plus any accrued interest thereon,” said the order, seen by AFP.
Otto Warmbier, an Ohio native who studied at the University of Virginia, travelled to North Korea on a tour in 2016.
He was pulled away from his group at Pyongyang airport and charged with crimes against the state for allegedly taking down a propaganda poster.
According to the 2018 ruling, when he finally returned home after 17 months, Warmbier was attached to a feeding tube and was howling incomprehensible noises.
Warmbier had gone blind and deaf, his once straight teeth were misaligned and his eyes bulged out, the ruling said.
He died six days later.
North Korea at the time blamed his condition on medicine they said he took for botulism.