China has vowed to crack down on companies that have been secretly channeling cash into the country after a surge in capital inflows.
The clampdown follows severe discrepancies in China's export data in the first quarter that aroused suspicions about Chinese companies using trade deals to evade capital controls and bring cash onshore.
China keeps a tight grip on foreign exchange flows in and out of the country, worried that speculators could fuel asset bubbles and inflation.
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But despite years of repeated campaigns to limit hot money, an apparent surge in Chinese exports in the first quarter, when other countries reported much weaker data, pointed to a resurgence in inflows. Analysts believe Chinese exporters were over-invoicing as a way of bringing more cash into the country covertly.
The State Administration of Foreign Exchange said it would issue warnings to companies that have serious mismatches between declared deal size and actual transactions in goods. If companies are unable to provide satisfactory explanations for the gaps, Safe will blacklist them and subject them to "strict supervision" until they demonstrate compliance with regulations.
Previously, the Chinese customs administration had rebuffed criticism of the export data, saying that faked trade declarations "were not mainstream".
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The SAFE statement, published late on Sunday, was the first significant action taken by the government to address the problem.
"This is clearly a sign that the authorities recognize that companies channeling inflows into China dressed up as exports is actually a serious issue, that it is happening and that they want to do something about it," said Louis Kuijs, an economist with the Royal Bank of Scotland.