The roughly 90-second video shows a government-built apartment block inundated with clutter, voiced over in a Singaporean accent.

"This happens right outside Singapore's doorstep too, in the South China Sea, where one neighbour thinks he owns basically everything," the narrator says, as the video cuts to a series of news clippings on China's territorial disputes.

The post sparked a strident reaction from China's embassy in Singapore late Wednesday.

On its Facebook page, the Chinese embassy said the video "deliberately distorts the ins-and-outs of the South China Sea issue".

"Under joint efforts of China and ASEAN countries, the current situation in the South China Sea remains overall stable," it added, referring to the Association of Southeast Asian Nations bloc.

The embassy said it was "universally recognized that the U.S. is the least qualified to even talk about international law".

Beijing claims almost the entire disputed waterway, through which more than 60 percent of global maritime trade passes, despite an international ruling that its assertion has no merit.

The South China Sea is also believed to contain valuable oil and gas deposits, and there are concerns that Beijing is seeking to expand its reach.

In Southeast Asia, Brunei, Malaysia, the Philippines and Vietnam have partial claims to the sea.

Singapore's foreign ministry said in a statement Wednesday that it rejects interference by foreign embassies.

"The Singapore Government rejects attempts by foreign embassies to incite domestic reactions to international issues involving third countries," the statement said.

"Complex issues are best resolved through appropriate channels for effective diplomacy," it said.