Trading of UK-listed financial firms in Hong Kong-HSBC, Prudential, and Standard Chartered-slumped Thursday after a Chinese media report said mainland residents now face tighter restrictions on opening offshore accounts at major Hong Kong banks, Reuters News reported on the same day.

The Bank of East Asia's Shanghai branch stopped opening overseas investment accounts for mainland clients, and HSBC's Lujiazui staff said deposited funds must comply with Hong Kong rules, the newswire reported, citing the South China Morning Post.

As a result, HSBC, Standard Chartered, and Prudential tumbled between 5% and 6.3% in London, and AIA Group dropped 6.8% in Hong Kong, the publication said.

HSBC, Prudential, and Standard Chartered were not immediately reachable for comment when contacted by Reuters, the report said.

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