Hong Kong's former finance chief John Tsang announced Thursday his bid to run for leader, promising to resolve conflict after a tumultuous period which has seen major anti-Beijing protests.

The city has become sharply divided under outgoing chief executive Leung Chun-ying, who opponents cast as a puppet of the Chinese government squeezing the semi-autonomous city's freedoms.

Nicknamed "Mr Pringles" for his resemblance to the crisp brand's mascot, a smiling Tsang, 65, held up his phone to reveal a cartoon sticker of himself in the style of the moustachioed Pringles icon as he announced his candidacy.

Tsang is seen as more moderate than Leung, but is still an establishment figure and slammed those seeking independence for Hong Kong as an "extreme minority".

He will go head-to-head with Leung's tough former deputy Carrie Lam, who is seen as Beijing's favoured candidate for the vote in March.

"What I fear most is that the confrontation and conflicts that we have seen in our society recently have eroded permanently our courage and confidence to seek solutions," Tsang said, adding that he wanted to garner support from across the political spectrum.

"Looking back on history, darkness always gives way to light," said Tsang, who served as finance secretary for nine years.

Describing the city as being at a "historic juncture" Tsang said he wanted to stem emigration as residents consider jumping ship because of political uncertainties, a widening wealth gap and sky-high housing costs.

He compared their anxiety to the atmosphere in the lead-up to Britain handing Hong Kong back to China in 1997, which prompted some residents to leave.

Having emigrated from Hong Kong as a teenager to live in the United States before returning in 1982, Tsang sought to bolster his patriotic credentials.

"You all may know that I have practiced martial arts since I was little -- but you may not know that while in the US I once was involved in a fight because a person insulted Chinese people to my face," Tsang said.

He also emphasised the importance of relations with China saying the city could benefit from "a motherland that is welcoming the great rejuvenation of the Chinese nation", a phrase often used by Chinese President Xi Jinping.

Democracy activists say whoever becomes the next leader will not truly represent Hong Kong because they will be chosen by a 1,200 member election committee made up of special interest groups skewed towards Beijing.

A Beijing-backed proposal which said the public could vote for their own chief executive but must choose from vetted candidates led to mass protests in 2014 and the plan was eventually voted down by pro-democracy lawmakers.

Since then, the political reform process has stalled.

When asked if he would kick-start it, Tsang said the government would need a "proper dialogue" to see if any compromise was possible.

"If we remain in our positions and won't budge a bit, it will not serve any purpose," he said.