PHUKET, Thailand — U.S. Secretary of State Hillary Rodham Clinton arrived at a key security conference today carrying a no-nonsense message that the United States is ready to re-engage with Asia after years of neglect.

Clinton, arriving from Bangkok, moved right into talks with Asian counterparts gathered for two days of international meetings to discuss North Korea, Myanmar and a range of other regional issues.

She said she will sign the seminal Treaty of Amity and Cooperation of the Association of Southeast Asian Nations, or ASEAN, a commitment to peacefully resolve disputes that already has been signed by more than a dozen countries outside the 10-nation bloc.

"The United States is back," she declared upon arrival in the Thai capital Tuesday.

And in an appearance this morning on a Thai TV talk show in Bangkok she said, "President Obama and I are giving great importance to this region," suggesting that the administration of former President George W. Bush neglected U.S. interests in Asia.

Evidence of the new U.S. approach, she said, is the fact that her first overseas trip, in February, was to Asia.

"I believe strongly the United States has to be involved in this region," she added.