Malaysia said it will block Israel-based ZIM Integrated Shipping Services from anchoring at any of the Southeast Asian nation’s ports, a largely symbolic move that signals rising frustration over the war in Gaza.

The country is also banning ships bearing Israeli flags, and will prevent vessels destined for Israel from loading cargo at its ports, Malaysian Prime Minister Anwar Ibrahim said in a statement Wednesday. The ban is effective immediately.

“These sanctions are a response to Israel’s actions ignoring the basic principles of humanity and breaking the international law through continued massacres and atrocities against Palestinians,” Anwar said. 

Malaysia is among the most vocal supporters of the Palestinians amid the ongoing war between Israel and Hamas, which is a designated terrorist group by the US and European Union. Last month, Anwar vowed to maintain ties with Hamas despite pressure from the US, which some political analysts say is an attempt to shore up his Islamist credentials in the Muslim-majority nation.

Israel’s economy relies on seaborne trade, but it is not a major flag state, with a total number of vessels that is dwarfed by far larger players such as Panama, Liberia and the Marshall Islands. A flag state has overall responsibility for the implementation and enforcement of international maritime regulation.

The Malaysian government has welcomed ZIM’s ships to the country since 2002, Anwar said. Reversing that decision will not hinder Malaysia’s trade activities, he added.

Almost 19,500 Palestinians have been killed in Gaza, according to the Hamas-run health ministry, alongside widespread destruction of homes and other infrastructure. About 1,200 people were killed when Hamas fighters stormed Israel after the initial incursion by Hamas fighters on Oct. 7. Israel has vowed to destroy Hamas to avoid any future attack.