US President Barack Obama on Saturday declared Washington's intent to renew its active role in the Asian region after being "disengaged" in recent years.
"As an Asia Pacific nation, the US expects to be involved in the discussions that shape the future of this region, and to participate fully in appropriate organisations as they are established and evolve," he said.
Obama was speaking to Japanese citizens, scientists and business people at Suntory Hall in Tokyo, a day after meeting Japanese Prime Minister Yukio Hatoyama.
Obama acknowledged that the US "has been disengaged" in recent years from regional organisations that promote security and prosperity in Asia, a clear reference to his predecessor George W Bush's rejection of international organisations.
"So let me be clear: those days have passed."