Lee told reporters that the "reckless imposition of tariffs affects many countries and regions around the world, with huge tax rate increases and covering a wide range of goods, disrupting the world economic and trade order, bringing great risks and uncertainties to the world".

The 13.2 percent rout of the benchmark Hang Seng Index the day before wiped trillions off company valuations as US President Donald Trump's trade war ramps up recession worries.

"The (United States) no longer adheres to free trade, arbitrarily undermining the internationally established rules of world trade," Lee told reporters on Tuesday morning.

"Its ruthless behaviour damages global and multilateral trade."

Lee said his government will boost its policies in seven areas, including tighter integration with China, seeking regional collaborations and supporting local businesses.

The city's financial secretary Paul Chan on Monday criticised the US tariffs as "bullying", adding that they would "inevitably increase market volatility".

The Chinese finance hub has not followed Beijing's lead in imposing retaliatory levies, with Chan saying that Hong Kong is committed to free trade.

The finance chief said Monday's market volatility did not warrant "drastic measures" from the government.