Malaysia has rejected China’s expansive maritime claims in the South China Sea in a rare public rebuke of its largest trading partner.

The government made a submission to the United Nations two weeks ago on its rights over the remaining portion of a continental shelf beyond 200 nautical miles from the country’s baselines, Foreign Minister Hishammuddin Hussein told Parliament on Thursday. It was in response to a similar claim China made to the UN on December 12, he said.

“Malaysia opposes China’s claim that they have historic rights over those waters,” said Hishammuddin.

“The Malaysian government also considers China’s claims over maritime features in the South China Sea to have no basis whatsoever under international law.” The rebuke is an unusual move for Malaysia, which had previously avoided reproaching China openly by reiterating its focus on ensuring the area remains open for trade. Its submission to the UN comes on the heels of Australia and the US rejecting China’s maritime claims in response to what the two allies see as an intensifying campaign to dominate the resource-rich area.