Although Washington has been reaffirming to Beijing across the discussion table that it has no interest in "decoupling" the US economy from that of China, its actions to the contrary have never ceased.

According to reports by the South China Morning Post, the United States has recently started requiring Hong Kong exporters to abide by the "unwritten rules", that they must not register companies in the Chinese mainland or the Hong Kong Special Administrative Region, but in Singapore, otherwise they will be fully boycotted by the US, even after they have relocated their factories from the mainland to Vietnam and other Southeast Asian countries.

According to these "unwritten rules", if exporters register their businesses in the mainland or Hong Kong, they will not obtain orders from the US.

That is in line with the overall "decoupling" Washington has been trying to realize in the US' economic and trade relations with China under the excuse of diversifying import sources to strengthen national security. Its intent is to force enterprises to relocate their industry chains out of China. But it is not that easy for the US to diversify its supply chains without China's involvement, because of China's indispensable role in the global supply chains.

China's core competitiveness is based on it being the only country with a comprehensive supply chain system and a comparatively complete industry system, as well as its large high-quality labor force, sound infrastructure and strong operating efficiency.

As a result, US importers are being caught in a dilemma by the US government's "unwritten rules". On the one hand, they cannot import from their Chinese suppliers, be they based in the mainland or Hong Kong, and on the other hand, the "decoupling" policies leave them nowhere else they can buy from.

US companies showed great enthusiasm for the first China International Supply Chain Expo that concluded last week in Beijing, accounting for 25 percent of the overseas exhibitors registered at the event, exposing their true attitude to the "decoupling".

Even if the US requires Hong Kong exporters to register companies in Singapore or anywhere else out of China, the impact will not be as large as it hopes. As long as the companies' manufacturing bases or industry chains are in China or related to it, or funded by China-related capital, which is often the case, no matter where they are registered, the profits will trickle down to the root source.

The US' "decoupling" practices are against the basic law of the market and the overall trend of economic globalization. US companies benefit the most from their branches elsewhere in the world, including China.

The development of the global industry and supply chains cannot be dictated by the will of politicians in Washington. What they are trying to do only adds unnecessary costs to the global economic system, with the US consumers as the final payers.