Macao plans to further restrict the use of China UnionPay debit cards at casinos to curb incoming money flows, which have dragged down gambling shares, the Hong Kong-based Wen Wei Po reported.

The Monetary Authority of Macao has ordered jewelry stores and pawnshops at casinos to remove UnionPay card terminals by July 1, according to local gaming companies.

The move is aimed at mainland tourists, some of whom are reportedly buying expensive items and exchanging them for cash.

Macao has cracked down on cashing out illegally with UnionPay card swipers and arrested 12 people in February and March.

Deputy Chairman of the HK-listed Success Universe Group Ltd., which runs gaming and entertainment businesses, said the change will make getting cash less convenient for VIP gamblers.

Nearly all casino stocks saw drops on Tuesday, with shares of SJM holdings, the city's biggest gambling company, slumping by 5.19 percent.

Tourists from mainland China can bring 20,000 yuan ($3,260) when traveling across the border, and withdraw as much as 10,000 yuan a day with each card at cash machines.