US President Barack Obama may be going to Copenhagen empty-handed when it comes to legislation on limiting emissions, but Washington can still claim to have seized the initiative on climate protection. A declaration by the Environmental Protection Agency declaring that greenhouse gases are a health hazard gave a huge boost to America's standing at the climate change conference.

On Monday, EPA Administrator Lisa Jackson signed orders classifying six greenhouse gases, including carbon dioxide, as pollutants that will now be subject to government regulation. The ruling would allow the EPA to use the Clean Air Act to regulate emissions, potentially side-stepping the need for climate change legislation which has stalled in Congress.

The announcement on the opening day of the 192-nation summit meeting in the Danish capital was greeted with a wave of enthusiasm by environmental campaigners. The Copenhagen meeting gathers together members of the UN Framework Convention on Climate Change with the aim of drafting an outline agreement of the successor treaty to 1998's Kyoto Protocol by the closing of the conference on Dec. 18. The goal of the treaty is to establish binding emissions cuts for major emitters in the coming decades and to establish provisions that would see richer industrialized countries helping to finance the technologies needed by developing nations to curb carbon emissions.

Yet no agreement will be possible without leadership from the US, which was clearly lacking under the previous Bush administration. While President Obama has sought to emphasis the stark difference from his predecessor on the issue of climate change, carbon-capping legislation that narrowly passed the US House of Representatives has now stalled in the Senate.

The EPA ruling, however, offers evidence that Obama is still hoping to contribute to solving climate change. Without action by the US, one of the world's biggest emitters of greenhouse gases, developing nations are unlikely to take the necessary steps to combat climate change.

German newspapers on Wednesday ponder whether Obama will succeed in persuading US lawmakers of the need to take urgent action, or will be forced to go it alone and regulate emissions.

The center-left Süddeutsche Zeitung writes:

"Of course it is no coincidence that the EPA decision, which was planned half a year ago, is being announced at the opening of the climate protection conference in Copenhagen. This is supposed to signal to the world that the new US government wants to follow its words with deeds and undertake concrete steps toward climate protection. The message has hit home: Environmental groups greeted the news from Washington with euphoria. Yet at the current time this is nothing more than symbolic. The limits have to be set. And that could take some time."

"It is a message to the Senate that the US administration is serious about its efforts towards climate protection. Climate protection legislation is being dragged through the Senate, which for the first time would significantly reduce the levels of emissions in the US. The White House is saying that legislation would be better than climate protection by decree. Any such order could be overturned by a successive administration. However, the message to the Senate is that at a pinch it will be done without them."

The center-right Frankfurter Allgemeine Zeitung writes:

"American President Obama has had a great idea: He has told his environmental agency to declare carbon dioxide as an environmental hazard. In this way he can force through the reduction in CO2 emissions, though the Senate has refused him a legal basis for such reductions. All of Copenhagen cheered this coup. The reactions in the US will be the opposite. If Obama cannot convince his own people that they are digging their own graves with their wasteful use of fossil fuels, then no tricks will help."

The left-leaning Die Tageszeitung writes:

"The Americans have succeeded in doing what they do best at climate talks: lowering expectations at the beginning only to arrive with great fanfare on the summit stage."

"Obama let the world guess for a long time if he was even going to Copenhagen... . In the end he postponed his appearance to the final decisive days of the climate summit. And now the EPA decision arrives right on time, though it has been expected in the US since spring."

"That is why it is important to recall some important facts: First, the US still hasn't ratified the Kyoto Protocol. Second, it has not kept its promises made at the Rio summit in 1990. Third, it is the country that emits by far the most greenhouse gases."