UN Secretary-General Ban Ki-moon says the US-backed climate deal is an essential beginning to creating a global agreement, but critics say it's a failure.
In last-minute talks before the summit ended, the United States, China, Brazil, India and South Africa agreed to the goal of emission cuts but set no targets; in any case, the conference as a whole did not adopt the so-called "Copenhagen Accord" negotiated by those five nations - it merely "noted" it.
The BBC reports that the prevailing mood at Copenhagen, as the summit broke up and delegates began heading home, is one of disappointment. Even US President Barack Obama, though claiming that the "foundation for international action in the years to come" has been laid, admits that not enough progress was made.
The five-nation accord is an essential beginning, Mr Ban says, but it must be made legally binding in Mexico next year.
The accord includes a recognition to limit temperature rises to less than 2 degrees celsius and promises to deliver $30bn of aid for developing nations over the next three years.
It outlines a goal of providing $100bn a year by 2020 to help poor countries cope with the impacts of climate change.
The agreement also includes a method for verifying industrialised nations' reduction of emissions.
Developing nations denounce five-nation deal
Many hours after the final session should have ended, delegates were still debating the five-nation deal. To be accepted as an official UN agreement, it had to be endorsed by all 193 nations at the talks.
Many supported it, but it was rejected by several developing nations outraged that no firm emissions targets had been set and, angry, too, at the way in which the deal had been done by a small group of nations.
The main opposition came from a bloc of Latin American countries, with the Venezuelan delegate saying the deal was a "coup d'etat against the authority of the United Nations".
Tuvalu negotiator Ian Fry said that Mr Obama's claim that a deal had been done was disrespectful of the UN process.
But the ABC reports that Australia's climate change minister Penny Wong has criticised the critics.
She says there are a few radical nations and states seeking to block action on climate change internationally and seeking to derail the process.