
Obama made the appeal at a historic gathering with Asean leaders, which included Burmese Prime Minister Thien Sein, following his speech in Tokyo on Saturday.
He also expressed appreciation at the progress Asean had made, according to high level sources present at the leaders' meeting.
Among other things, the US president called for a national reconciliation dialogue with all stakeholders and an inclusive, free and fair election in Burma.
Obama and the leaders of the 10-member Southeast Asian bloc agreed that the junta-run election next year must be "free, fair, inclusive and transparent" to be credible.
The sources said the Burmese prime minister did not respond to Obama's appeal, and instead talked about nuclear non-proliferation.
The sources said Obama was very upbeat on Asean and its prospects following introductory remarks by co-chair Prime Minister Abhisit Vejjajiva.
The Thai leader kicked off the 90-minute discussion by reviewing Asean-US relations over the past 32 years. He expressed appreciation at the US signing the Treaty of Amity and Cooperation and the newly established ministerial conference between the US and Lower Mekong countries.
Abhisit also expressed gratitude to the US government for supporting the Asean Intergovernment Commission on Human Rights by inviting its members to meet with their American colleagues.
The US president, who praised Abhisit's able chairmanship of Asean, pointed out that Asean is an organisation of "global importance" and that the US views Asean as a "valued and trusted" partner, the sources said.
In their first meeting, Obama indicated that the US does not want to be just a dialogue partner but also a member of the Asean family. He said the US supports the integration of the Asean Community in 2015.
Obama responded to Abhisit's introductory remarks by saying that the future of community building in the region would be an inclusive and open one. Washington has made it known that it is interested in being a part of the new regionalism.
There were signs of disappointment among the Asean leaders, according to the sources, when Obama did not endorse the regular attendance of the Asean chair at the G-20 summit as anticipated. Instead, he expressed appreciation for the role and contribution of the Asean chair at G-20 summits.
As the Asean chair, Abhisit attended both the London and Pittsburgh G-20 summits. The next summit will be held in South Korea in April.
The historic first Asean-US Leaders' Meeting, in recognition of Asean's growing capacity and role in global issues, concluded with an agreement on the importance of continuing dialogue at the highest level between the two sides.
Washington will support Asean's continuing role in multilateral efforts where Asean has a growing ability to make contributions, their joint statement said.
"The president of the United States also supported regional efforts initiated by Asean and Asean-led fora, to address the impact of the global financial and economic crisis in the region, and looked forward to continued close coordination between such regional efforts and the global efforts undertaken by the G-20," it said.
The US will establish its permanent office for Asean in Jakarta during the first half of next year.
Towards the end of their meeting, Obama instructed US authorities to follow up on the proposals and plan of action mentioned in the joint statement. He said he and the US secretary of state expect a full report on the progress made before he meets the Asean leaders again next year.
Both sides agreed to touch bases next year, with Vietnam offering to host the next leaders' meeting.