Lam takes office on July 1 after being selected in March amid widespread concern that Beijing's meddling had sealed her victory and denied the freewheeling former British colony a more popular leader.

The former civil service chief replaces her former boss, incumbent Chief Executive Leung Chun-ying, a deeply unpopular leader widely viewed in the city as being too eager to please Beijing's Communist Party leadership.

Those leaders are increasingly fearful that a fledgling independence or secessionist movement in Hong Kong could spread, and a Beijing official based in the city warned at the weekend that further trouble could threaten its vaunted autonomy.

The city was promised widespread freedoms and legal protections under a "one country, two systems" formula agreed when Britain handed it back to Chinese sovereignty in 1997.

Acknowledging tension and the city's restive youth, Lam said she was aware of the city's problems and deeply polarized views.

"I will do my utmost to unify society and to bring Hong Kong back to its normal course of development, because I think that is the aspiration of the great majority of Hong Kong people," said Lam, who will become Hong Kong's first female leader.

She said her election manifesto had emphasized the need to address the aspirations and "unhappiness" of young people with greater opportunities and upward mobility.

"So together with my team from July 1, that is going to be one of our policy priorities."

Lam offered no fresh specifics on any new policies or views on political reform but she has previously said that unifying society was a key goal, besides improving livelihoods and the city’s troubled governance.

Many of the city's pro-democracy opposition and activists were opposed to Lam's selection by a 1,200-person election panel stacked with pro-Beijing and pro-establishment loyalists, who spurned the more popular candidate, former government financial chief John Tsang.

She faces widespread fears that Hong Kong's freedoms are under threat and must tackle soaring property prices that are, in part, driving divisions and widening an extreme wealth gap.

Part of the public mistrust of Lam stems from her previously close working ties with Leung, who ordered tear gas to be fired at pro-democracy protesters in late 2014, during the long-running 'Occupy' civil disobedience movement.