LOS ANGELES, May 15 (Xinhua) -- Los Angeles Mayor Antonio Villaraigosa Tuesday released a plan aimed at significantly reducing greenhouse gas emissions in one of the most polluted cities in the United States.

    The plan, dubbed Green LA, relies heavily on 50 initiatives aimed at expanding renewable energy sources and providing alternatives to driving vehicles, with a target to reduce the city's carbon dioxide emissions 35 percent below 1990 levels by 2030.

    "We're setting the green standard in L.A.," Villaraigosa said. "Reducing our carbon footprint by 35 percent below 1990 levels is the most ambitious goal set by a major American city."

    Los Angeles once again topped the list of the most polluted U.S. cities in a study released by the American Lung Association earlier this month.

    The new green plan calls for expanded regional rail lines, improved bus service to Los Angeles International Airport, more development around transit hubs, and distributing fluorescent light bulbs as a way to urge residents to conserve energy.

    And the mayor also wants to secure 35 percent of the Los Angeles Department of Water and Power's energy from renewable sources by 2020.

    The city utility, which supplies electricity for 1.4 million homes and businesses, currently relies heavily on burning coal at power plants and is responsible for one-third of the total emissions.

    Villaraigosa is scheduled to visit New York on Wednesday, when he will address leaders of some of the world's largest cities at ameeting on how to combat climate change, hosted by New York Mayor Michael Bloomberg and former U.S. President Bill Clinton.

    California Governor Arnold Schwarzenegger has touted a state law that calls for a 25 percent reduction in carbon dioxide emissions by 2020.

    The efforts in California exceed mandates outlined in the Kyoto Protocol, a 1997 agreement to reduce greenhouse gases that is backed by more than 170 countries, but not the United States. Washington has refused to join the treaty.