Pro-democracy protesters in Hong Kong warned on Wednesday that they will step up their actions if the territory's leader, Chief Executive Leung Chun-ying, doesn't resign by the end of Thursday.

Protesters leaders, of what has become known as the "umbrella revolution," have threatened to occupy several important government buildings, putting themselves at risk of further confrontation with police.

Vice Secretary of the Hong Kong Federation of Students Lester Shum said, however, that demonstrators would not occupy "essential" government offices, such as hospitals and social welfare offices.

'No room for dialogue'

At a news conference on Wednesday, Shum said he would welcome the chance to speak to a Chinese central government official.

"However, we ask them to come to the square and speak to the masses," Shum said. "This is a movement of Hong Kongers and not led by any specific group."

Shum went on to demand Leung's resignation, saying there was "no room for dialogue" because Leung ordered police to fire tear gas at protesters over the weekend, after a week-long demonstration.

Some 100 participants already attempted to storm a government building on Friday, prompting police to respond with pepper spray.

Leung, however, showed no signs of resigning at a flag raising ceremony in Hong Kong on Wednesday to mark China's National Day. He told crowds that the recently adopted method of selecting the territory's next chief executive is a positive development.

'Illegal gathering'

Beijing's response to the protests had been mostly silent. On Tuesday, however, Chinese President Xi Jinping branded the protests as "illegal" and said "all tumors frown on the healthy organism" of the communist party must be removed.

The on-going demonstrations come in response to Beijing's plans to exercise more influence over the island region's leadership ahead of the 2017 election, which would see only Beijing-approved candidates being able to stand.

The former British colony has enjoyed special rights since it was reabsorbed by China in 1997, under a "one country, two systems" principle. According to that formula, universal suffrage is set as the eventual goal.

ksb/kms (dpa, AP)