This undated photo shows the building of the Hong Kong Monetary Authority. (PHOTO / IC)

The Hong Kong Monetary Authority bought HK$8.07 billion ($1.03 billion) from the market in New York trading hours to stop the local currency weakening and breaking its peg to the US dollar.

The Hong Kong dollar is pegged to a tight band of between 7.75 and 7.85 versus the US dollar.

The aggregate balance - the key gauge of cash in the banking system - will decrease to HK$191.317 billion on July 20, an HKMA spokeswoman said on Tuesday.

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