Authorities in Beijing are gathering financial intelligence on big-spending conglomerates - including the buyer of NZ finance company UDC.
Banking regulators ordered lenders to report on companies that have spearheaded Chinese international expansion with hundreds of billions of pounds of debt-fuelled acquisitions in recent years.
The China Banking Regulatory Commission (CBRC) requested information on exposure to Dalian Wanda, which owns Odeon Cinemas and the yacht builder Sunseeker, and Fosun, which last year acquired Wolverhampton Wanderers.
HNA Group, a Chinese conglomerate which announced plans to buy Kiwi financier UDC in January for $660 million, is also in the regulators' sights.
UDC did not wish to comment when approached today.
The CBRC said it was interested in "systemic risks" to the financial system but did not comment on its specific aims. Liu Zhiqing, deputy director general of the prudential regulation bureau of the CBRC, said: "Some big companies are indeed the focus of our attention on systemic risks, because a big company has big risk exposure for banks and they could transmit to other companies."
It was claimed that the curtain could be brought down on major international takeovers by Chinese groups.
The developments knocked Western stocks already owned by China's conglomerates. They included Thomas Cook, in which Fosun holds an 8.2 per cent stake. The tour operator's shares ended the day down 2.8 per cent. It is understood that Thomas Cook contacted Fosun and was told there was nothing to worry about. The response echoed public statements that "everything is going well and normal with Fosun".
Gemfields, the London-listed owner of Faberge, which this week recommended a £256m takeover bid from Fosun, slipped more than 4 per cent over concerns the deal could be obstructed by events in Beijing.
Deutsche Bank, in which HNA has built up a 10 per cent stake, dipped by 1per cent in Frankfurt. Hilton Hotels, a quarter owned by the same group, was down in New York.
Observers saw the CBRC's moves as the latest effort by the Chinese government to curb the frantic pace of outbound takeover activity. Capital controls introduced in 2014 have been relaxed, but authorities have signalled more scrutiny of the country's most enthusiastic dealmakers.
This month Wu Xiaohui, the chairman of Anbang, was barred from international travel and then detained for questioning over the insurer's US$30b spending spree.
The scrutiny appears to have had an effect. Outbound investment by Chinese companies in the first five months of the year was less than half last year's figure, according to China's commerce ministry. Overseas deals by Chinese companies hit a record US$170b in 2016.
Unconventional financing techniques and government pressures have made some Western authorities and dealmakers wary of Chinese bidders.
HNA lost out in the battle to buy City Airport last year, despite tabling a higher offer than the ultimate winner. Fosun meanwhile abandoned a bid for the merchant bank Kleinwort Benson after receiving financial transparency demands from British regulators.