Financial regulators have called top bankers in Macau to a key meeting next month as part of a Beijing-inspired dirty-money crackdown that has rocked the city's under-pressure casino sector and sent gaming stocks tumbling. In a note sent out late on Tuesday, Monetary Authority chiefs told city bankers they would "explain a live monitoring system" which the South China Morning Post yesterday revealed will give Beijing's powerful Ministry of Public Security unprecedented access to all transfers through the state-backed China UnionPay bank payment card. All Macau casino stocks dropped in trading yesterday in the wake of news of the crackdown, which comes just 48 hours before President Xi Jinping arrives in Macau to lead ceremonies marking the 15th anniversary of the former Portuguese enclave's return to Chinese sovereignty. Galaxy Entertainment Group suffered the most, dropping 8.2 per cent, while MGM China fell 7 per cent and Sands China 6.18 per cent. SJM Holdings dropped 6.17 per cent and Wynn Macau by 4.30 per cent while Melco Crown Entertainment was down 3.86 per cent. In comparison, the benchmark Hang Seng Index lost 0.37 per cent. The note sent to banks, seen by the Post , also asked banks to provide a list of names and information on high-risk businesses who use the China UnionPay bank card system. These include stores selling watches and jewellery, wine, pharmaceutical products, dried seafood and telecommunications businesses, the note said, adding that "high-risk businesses" in nearby casinos were also included. The key involvement of the ministry's Economic Crimes Investigation Bureau - which is spearheading the "Fox Hunt" operation aimed at securing the return of corrupt party officials who have fled overseas - provides confirmation of the long-held belief by many that Macau casinos are a major conduit for capital flight from the mainland. A senior gaming insider said yesterday: "This is causing a lot of concern; it seems Beijing means business, and it's not just the VIP junket operators who bring in the high-rollers who are nervous." The latest move deals another blow to the gaming industry following six months of declining revenue, due in large part to Xi's "tigers and flies" anti-corruption drive. Analysts forecast a year-on-year drop of around 20 per cent this month that will push the city to register its first full-year casino revenue decline. It is unclear how deeply the new measure will affect VIP volumes, Bloomberg gaming analyst Tim Craighead said. However, he added that the news comes in a month when institutional investment managers review their year-end portfolios. "If there's even more concern, do they want to back off positions? It can have an amplified impact," he said.