“The court therefore orders the State to put an end to the further export of F-35 parts to Israel within 7 days,” said the ruling.
“There is a clear risk that serious violations of humanitarian law of war are committed in the Gaza Strip with Israel’s F-35 fighter planes,” added the judge.
The US-owned F-35 parts are stored at a warehouse in the Netherlands and then shipped to several partners, including Israel, via existing export agreements.
In December, the District Court in The Hague had said that supplying the parts was primarily a political decision that judges should not interfere with.
“The considerations that the minister makes are to a large extent of a political and policy nature and judges should leave the minister a large amount of freedom,” the court ruled at the time.
But the appeals court overturned this ruling, saying the Netherlands “must prohibit the export of military goods if there is a clear risk of serious violations of the humanitarian law of war.”
“Israel does not take sufficient account of the consequences for the civilian population when conducting its attacks,” said the court.
The attacks in Gaza “have caused a disproportionate number of civilian casualties, including thousands of children.”
The war was launched in response to the unprecedented attacks on Israel by Palestinian militant group Hamas on October 7.
Those attacks resulted in the deaths of around 1,160 people, mostly civilians, according to an AFP tally based on official Israeli figures.
Militants also seized about 250 hostages, according to an AFP tally based on official Israeli figures. Israel says around 130 are still in Gaza, though 29 are thought to be dead.
Israel has responded with a relentless offensive in Gaza that the territory’s Hamas-run health ministry says has killed at least 28,340 people as of Monday, mostly women and children.