HONG KONG (AFP) - Pro-democracy protesters on Monday (Feb 27) gatecrashed a press conference by Hong Kong leadership hopeful Carrie Lam, displaying banners criticising a "rigged election" as the woman seen as China's favourite unveiled her policy.

Around a dozen activists including Joshua Wong, the face of 2014's mass pro-democracy protests, entered the venue minutes before the start and demanded to be allowed to communicate their messages to Lam.

Protesters chanted slogans and unfurled banners demanding the public get the right to vote for the city's top post.

They were allowed to stay after campaign manager Bernard Chan said he welcomed them to sit in.

The chief executive of the semi-autonomous Chinese city will be chosen on March 26 by a 1,200-strong committee, most of whose members are broadly pro-Beijing.

Lam, a former deputy leader of the Hong Kong government, was in charge of promoting a Beijing-backed political reform package rejected as a sham by the pro-democracy camp in 2014.

The proposal would for the first time have allowed all Hong Kong voters to elect their leader, but would tightly control those eligible to stand.

Lam said Monday that divisions in society had made it difficult to restart discussions about political reform.

Her platform instead focused on livelihood issues, the city's housing crisis, the economy and youth development.

After the event Lam approached the protesters and presented her campaign pamphlet. Some demonstrators tore it up and threw pages at her.

Lam and her colleagues eventually left hurriedly while the media and protesters surrounded them.

Lam's campaign said she had garnered more than 400 nominations from members of the election committee - a minimum of 150 are needed - and would formally submit her candidacy on Tuesday (Feb 28).

Former financial secretary John Tsang, who has won support from some members of the pro-democracy camp, and ex-judge Woo Kwok-hing have secured 160 and 180 nominations respectively, local media reported.