Two major planned projects -- Chinese Petroleum Corp.'s petrochemical complex in southern Taiwan and Formosa Plastic Group's steel mill -- are likely to be subjected to any new regulations.

"If the consensus is that all major investment projects will be required to undergo evaluation then, from today, all projects will have to adhere to it, including Formosa Plastics and others," Economics Minister Ho Mei-yueh told a conference that concluded late on Tuesday.

Media has speculated the projects could be delayed ahead of implementing the tougher emissions laws.

State-run Chinese Petroleum plans to build a T$370 billion ($11.8 billion) complex with a 300,000-barrel-per-day refinery and a naphtha cracker with an annual capacity of 1.2 million tonnes of ethylene. Formosa Plastics plans to invest T$130 billion ($4.1 billion) to build a 7.5 million tonne-per-year steel plant nearby.

Taiwan's government is trying to steer a course between satisfying increasingly vocal residents' demands for a cleaner environment while not overly curtailing industrial growth.

Without any action, the government estimates annual CO2 emissions from the island of 23 million people could almost double to 530 million tonnes by 2025.

It hopes its proposed policy will reduce CO2 emissions in 2025 by 170 million tonnes.

"I hope this is just the first step," Ho said. "How much of the goals we can attain depends on resolving some technical issues and discussions with industry."

Part of the proposed guidelines could include requiring firms to submit plans showing how they will meet as-yet unspecificed emission reduction goals and increase their energy efficiency.

Another measure could be a cap-and-trade plan, whereby the government caps overall emissions and allows firms to buy additional volumes from companies that would not hit their annual limits. Another is a tax on carbon emissions.

Taiwan is ranked 22nd in the world in terms of CO2 emissions, the government says, accounting for approximately 1 percent of global emissions.

Environmentalists criticised the draft, saying the government offered no concrete proposals and its failure to offer comprehensive estimates of the growth in greenhouse gases made the reduction targets meaningless.

They also noted the failure of a previous plan to cut emissions formulated in 1998 despite moving towards greater reliance on natural gas, which pollutes less than oil.