The United Nations’ highest court has ordered the United States to lift sanctions on Iran that affect imports of humanitarian goods and products, and services linked to the safety of civil aviation.

President Donald Trump moved to restore tough US sanctions in May after withdrawing from Tehran’s nuclear accord with world powers. Iran challenged the sanctions in a case filed in July at the International Court of Justice.

In a preliminary ruling in the case, the court said on Wednesday that Washington must “remove, by means of its choosing, any impediments arising from” the re-imposition of sanctions to the export to Iran of medicine and medical devices, food and agricultural commodities and spare parts and equipment necessary to ensure the safety of civil aviation.

The US is expected to challenge the court’s jurisdiction in a future hearing.

Last month, in its first legal response to the suit, US had told UN judges that they had no jurisdiction to rule on Tehran's demand for them to order the suspension of debilitating the nuclear-related sanctions.

UN court ruling on US sanctions shows Tehran is 'right': Iran

Tehran welcomed the ruling by the UN's top court as a “clear sign” that “Iran is in the right”.

The ruling by the International Court of Justice “once again shows that the US government [...] is day by day becoming more isolated”, the foreign ministry said in a statement.

It said the court had found that the crippling sanctions reimposed by Washington after it abandoned a landmark 2015 nuclear deal between major powers and Tehran were illegal.

“World public opinion and all independent countries will, with peace of mind, strive... to keep and carry out the JCPOA,” it added, using the official acronym for the agreement.

Foreign Minister Mohammad Javad Zarif called the court ruling “another failure for sanctions-addicted US government and victory for rule of law”.

“Imperative for int'l community to collectively counter malign US unilateralism,” he added in a tweet.