Hong Kong Chief Executive Carrie Lam has described herself as an administrator who does not understand politics, saying she could not have predicted the 2019 turmoil that erupted from the now-shelved extradition bill, it was reported on Friday.

The bill was sparked by the case of Chan Tong-kai, a Hongkonger wanted in Taiwan on suspicion of murdering his girlfriend in Taipei in February 2018, reports the South China Morning Post (SCMP) newspaper.

Since there was no extradition agreement between the two places, Hong Kong could not send Chan back to Taiwan.

The case was cited as a major reason for pushing forward legislation that would have allowed suspects to be sent to jurisdictions Hong Kong lacked an extradition agreement with, including mainland China.

It was eventually shelved in September 2019, but the protests against it evolved into months of social unrest, and violent clashes between radicals and police.

"I really did not expect it, because I don't consider myself to be a person who understands politics very well, I am an administrator," Lam said during a conversation with Phoenix Satellite Television, when asked if she ever expected Hong Kong politics to be so complex in her role as Chief Executive.

"But as of now, Hong Kong needs to have good governance, which is inseparable from politics."

Lam also said that it was her duty to uphold the "one country, two systems" principle under which Hong Kong is governed, and added her family trusted her 100 per cent because "they know what I'm doing is right".

Since Beijing imposed its national security law on Hong Kong on June 30, international pressure has mounted on Lam.

But while critics have said that the controversial law, which is aimed at punishing acts of secession, subversion, terrorism, and collusion with foreign forces to endanger national security, could be used to suppress dissent and undermine freedoms in the city, Lam has insisted the new law had restored calm.

"It brought back the Hong Kong we were once familiar with," she was quoted as saying in the interview by the SCMP newspaper..