Hong Kong and Macau are located at the east and west sides of the Pearl River Delta respectively, with a close distance of about 64 kilometres (40 mi) in between.

[citation needed] Hong Kong became the first European colony in East Asia occupied by the Portuguese Empire as Tamão in the early 16th Century.

The Portuguese were defeated by the Ming Empire in Hong Kong in 1521, and eventually took Macau as their settlement at the Pearl River Estuary as a replacement in 1557 until 1999.

Eventually Hong Kong developed as one of the busiest entrepots and financial centres while Macau became a world gambling capital.

The spokesman of the Civic Party urged Hong Kong Chief Executive Carrie Lam Cheng Yuet-ngor to express their concerns with Macau and demand an explanation.