Aides told reporters the discussion was "constructive," and focused on emissions goals from all key countries, verification mechanism and financing.
According to a pool report, when asked if Obama and Wen had achieved a breakthrough, the official said "they took a step forward and made progress."
Another administration official told reporters multilateral meetings are continuing, saying: "Different people are floating different drafts."
In his speech this morning, Obama said the time for talk as over and acknowledged that things have dragged on for decades.
This is the bottom line: We can embrace this accord, take a substantial step forward, continue to refine it and build upon its foundation. We can do that, and everyone who is in this room will be part of a historic endeavor -- one that makes life better for our children and our grandchildren.
Or we can choose delay, falling back into the same divisions that have stood in the way of action for years. And we will be back having the same stale arguments month after month, year after year, perhaps decade after decade, all while the danger of climate change grows until it is irreversible.
Ladies and gentlemen, there is no time to waste. America has made our choice. We have charted our course. We have made our commitments. We will do what we say. Now I believe it's the time for the nations and the people of the world to come together behind a common purpose.
We are ready to get this done today -- but there has to be movement on all sides to recognize that it is better for us to act than to talk; it's better for us to choose action over inaction; the future over the past -- and with courage and faith, I believe that we can meet our responsibility to our people, and the future of our planet.
In September, Obama used similar language when speaking at the United Nations Climate Change Summit. He said for too long the world was used to seeing inaction from the United States and that those days were over.
After touching down at 9:01 a.m. local time, President Obama joined these leaders for a multilateral meeting.
Obama met with Australian Prime Minister Kevin Rudd, United Kingdom Prime Minister Gordon Brown, French President Nicolas Sarkozy, Danish Prime Minister Lars L. Rasmussen, German Chancellor Angela Merkel, European Commission President Jose Manuel Barroso, Japanese Prime Minister Yukio Hatoyama, Chinese Vice Foreign Minister He Yafei, Ethiopian Prime Minister Meles Zenawi, Prime Minister of Bangladesh Sheikh Hasina, Brazilian President Luiz Lula da Silva, Russian President Dmitry Medvedev, Indian Prime Minister Manmohan Singh, South African President Jacob Zuma, Mexican President Felipe Calderon, Spanish Prime Minister Jose Luis Rodriguez Zapatero, South Korean President Lee Myung-bak, Norwegian Prime Minister Jens Stoltenberg and Colombian President Alvaro Uribe.
The White House has been approaching the issue with an all-hands-on-deck mentality - blanketing the summit with members of the Green Cabinet and framing climate change as something which affects everything.
Among the aides on board Air Force One were National Security Adviser Jim Jones. Cabinet Secretaries from Hillary Clinton to Tom Vilsack have spoken to the summit in recent days to make the case for global cooperation.
Early reviews of the Obama speech were not glowing, with most groups urging the U.S. to do more.
"Obama has said nothing to save the Copenhagen conference from failure," Raman Mehta of ActionAid said. "The US is the one major player yet to move. Developing countries have come here to negotiate in good faith but feel they have been cheated and it looks like they will leave empty handed."
WWF President and CEO Carter Roberts applauded Obama for setting out building blocks of a deal, but said "that's not enough to knit together the world community at this pivotal hour."
"As the President has said numerous times, all countries need to stand behind their commitments and agree to make those commitments transparent," Roberts said. "That applies to the US as well. The only way the world can be sure the US is standing behind its commitments is for the President to clearly state that climate change will be his next top legislative priority."
NRDC put out a more positive statement, saying "there is still time" to reach an accord and thanking Obama for "rolling up his sleeves."
Here's Obama's speech: