The CEO's summons to face the cross-party Foreign Affairs Committee came after former Hong Kong lawmaker Ted Hui criticised HSBC for blocking his local bank accounts.

The bank is complying with its legal obligations and is "not in a position to judge the motives" of Hong Kong police, Quinn told lawmakers questioning him over the lender's freezing of bank accounts of Hui and other pro-democracy politicians in the Asian city.

"I can't cherry-pick which laws to follow," Quinn said, adding that the bank would have to comply with police requests in any country in the world.

When pressed by lawmakers whether HSBC would ever deny police requests on ethical grounds, Quinn said he was not considering this in Hong Kong.

"If you're asking, am I willing to walk away from Hong Kong? The answer is no. We're too committed through our history and heritage."

Quinn had written to Hui, in a rare move by a bank boss to an individual customer, to argue that the bank had no choice and was complying with a police request.

The grilling from British lawmakers saw HSBC yet again dragged into the political battle between Hong Kong's pro-Beijing and Democratic factions, as well as the wider tensions between China and the West over the city's future.

Founded in Hong Kong but headquartered in Britain, HSBC has historically tried to remain politically neutral.

Recently however it has shown support for Beijing, most notably last June when its top executive in Asia signed a petition backing China's imposition of a national security law on Hong Kong.

Police in Hong Kong, as in most places in the world, have long been able to request customer information from banks and ask that accounts be frozen as part of criminal investigations.

Authorities are also scrutinizing the financial records of pro-democracy activists as they crack down on political opposition, Reuters reported earlier on Tuesday.

HSBC's lawyers believe a separate national intelligence law passed in 2017, which requires companies to assist China's state intelligence operations, "has no extraterritorial reach", the bank's head of compliance Colin Bell said.

That means the bank would not for example send information about individual British-based bank accounts to China, he said in response to lawmakers' questions.

(Reporting by Lawrence White and Iain Withers; Editing by Bernadette Baum and Jan Harvey)

By Lawrence White and Iain Withers