RIO DE JANEIRO, Dec. 21 (Xinhua) -- Brazilian President Luiz Inacio Lula da Silva on Monday criticized Washington's weak performance at the UN climate change conference in Copenhagen.

    The United States is not doing much for the planet, Lula commented in his weekly radio program.

    The United States did not ratify the Kyoto Protocol and the country only set a goal to reduce its carbon emissions by 4 percent compared with 1990 levels, which is too little, he said.

    Everybody knows that developed countries started polluting the atmosphere long before Brazil, China, India, and other countries, said Lula.

    The purpose of the Copenhagen conference was not to simply point out who was guilty, but to find a solution to the problem and take measures to stop global warming, he added.

    Climate change should be a priority for all world leaders, so that a solution can be found, he said. He was also optimistic that the leaders would find common ground in the near future.

    "Until the next meeting in Mexico, we must reach an agreement that defines a worldwide policy on the global warming issue," he said.