Other business leaders also support proposal, saying it will bring long-awaited political rights

Hong Kong's economy will suffer if opposition lawmakers fail to support the government's constitutional reform proposal, tycoon Li Ka-shing warned on Wednesday.

Li said the city and its residents faced inestimable losses if the proposal was killed by lawmakers, noting the retail and hospitality sectors were already suffering.

Hong Kong is counting the days to a historic vote to implement long-awaited political reforms that will grant 3.5 million registered voters living in the former UK colony the right to elect its leader for the first time.

Opposition lawmakers in the city have vowed to veto the proposal at a vote on June 17. They say the plan lacks genuine democracy, despite featuring democratic hallmarks such as universal suffrage and a secret ballot.

Li said the opposition's tactics would lead to increased livelihood problems.

Business conditions in Hong Kong's private sector slumped for a third month in a row to levels not seen since 2011, as business and investment from the mainland dropped to global financial crisis levels, according to HSBC.

Li's remarks, made outside his Hong Kong headquarters, echoed statements by fellow tycoons - collectively responsible for large areas of the local economy.

Movers and shakers in the financial hub have been increasingly vocal, calling for a handful of moderate opposition lawmakers to "stand on the side of wisdom" and give pro-government legislators the support to endow the city with long-awaited political rights.

Henderson Land Development Chairman Lee Shau-kee said the package of proposals would be a huge boost to business confidence, anticipating the local stock exchange could soar well above 30,000 points and pledging to donate HK$1 billion ($128 million) to charitable causes if the proposal passes.

Former Wharf chairman Peter Woo Kwong-ching has appealed to less radical opposition members to "side with public wisdom" in supporting the package.

Woo, a Standing Committee member of the Chinese People's Political Consultative Conference National Committee, has hit out at what he calls opposition misinformation, saying that the proposal offers genuine universal suffrage for the city's next leader.

K Wah Group Chairman Lui Che-woo, observing that divisions over the reform package have led to social conflicts eroding the city's competitiveness, called for a win-win solution on political reform.

The Galaxy Entertainment Group stressed that harmony was a prerequisite for prosperity in Chinese culture.

In a recent opinion poll, six of the city's major business chambers found that 90 percent of 2,561 members supported the reform proposals, which respondents said would underpin continued and stable development of Hong Kong's economy and social well-being.