BANGKOK (AP) -- On the eve of his landmark trip to Myanmar, President Barack Obama tried to assure critics that his visit was not a premature reward for a long-isolated nation still easing its way toward democracy.
"This is not an endorsement of the government," Obama said Sunday in Thailand as he opened a three-country dash through Asia. "This is an acknowledgement that there is a process under way inside that country that even a year and a half, two years ago, nobody foresaw."
Obama was set to become the first U.S. president to visit Myanmar, with Air Force One scheduled to touch down in Yangon on Monday morning. Though Obama planned to spend just six hours in the country, the much-anticipated stop came as the result of a remarkable turnaround in the countries' relationship.
The president's Asia tour also marks his formal return to the world stage after months mired in a bruising re-election campaign. For his first postelection trip, he tellingly settled on Asia, a region he has deemed the region as crucial to U.S. prosperity and security.
Aides say Asia will factor heavily in Obama's second term as the U.S. seeks to expand its influence in an attempt to counter China.
China's rise is also at play in Myanmar, which long has aligned itself with Beijing. But some in Myanmar fear that China is taking advantage of its wealth of natural resources, so the country is looking for other partners to help build its nascent economy.
Obama has rewarded Myanmar's rapid adoption of democratic reforms by lifting some economic penalties. The president has appointed a permanent ambassador to the country, also known as Burma, and pledged greater investment if Myanmar continues to progress following a half-century of military rule.
Obama's administration also reopened a USAID mission in Myanmar earlier this year. During his stop Monday, the president is expected to announce $170 million in funding over the next two years for a democracy program led by the mission.
Administration officials say the turnaround in Myanmar marks the most successful implementation of the type of engagement Obama pledged in his inaugural address, when he told rogue nations that the U.S. "will extend a hand if you are willing to unclench your fist."
But some human rights groups say Myanmar's government, which continues to hold hundreds of political prisoners and is struggling to contain ethnic violence, hasn't done enough to earn a personal visit from Obama.
Speaking from neighboring Thailand, Obama said Sunday he was under no illusions that Myanmar had done all it needed to do. But he said the U.S. could play a critical role in helping ensure the country doesn't slip backward.
"I'm not somebody who thinks that the United States should stand on the sidelines and not want to get its hands dirty when there's an opportunity for us to encourage the better impulses inside a country," Obama said during a joint press conference Sunday with Thailand's prime minister.
Even as Obama turned his sights on Asia, widening violence in the Middle East competed for his attention.
Obama told reporters Sunday that Israel had the right to defend itself against missile attacks from Gaza. But he urged Israel not to launch a ground assault in Gaza, saying it would put Israeli soldiers, as well as Palestinian citizens, at greater risk and hamper an already vexing peace process.
"If we see a further escalation of the situation in Gaza, the likelihood of us getting back on any kind of peace track that leads to a two-state solution is going to be pushed off way into the future," Obama said.
The ongoing violence is likely to trail Obama as he makes his way from Thailand to Myanmar to Cambodia, his final stop before returning to Washington early Wednesday.
Obama will meet separately in Myanmar with Prime Minister Thein Sein, who has orchestrated much of his country's recent reforms. The president will also meet with longtime Myanmar democracy activist Aung Sun Suu Kyi in the home where she spent years under house arrest.
The president, as he seeks to assuage critics, has trumpeted Suu Kyi's support of his outreach efforts, saying Sunday that she was "very encouraging" of his trip.
The White House says Obama will express his concern for the ongoing ethnic tensions in Myanmar's western Rakhine state, where more than 110,000 people -- the vast majority of them Muslims known as Rohingya -- have been displaced.
The U.N. has called the Rohingya -- who are widely reviled by the Buddhist majority in Myanmar -- among the world's most persecuted people.
The White House says Obama will press the matter Monday with Thein Sein, along with demands to free remaining political prisoners as the nation transitions to democracy.
The president will cap his trip to Myanmar with a speech at Rangoon University, the center of the country's struggle for independence against Britain and the launching point for many pro-democracy protests. The former military junta shut the dormitories in the 1990s fearing further unrest and forced most students to attend classes on satellite campuses on the outskirts of town.
Obama began his Asian tour on a steamy day in Bangkok with a visit to the Wat Pho Royal Monastery. In stocking feet, the president and Secretary of State Hillary Rodham Clinton walked around a golden statue of a sitting Buddha. The complex is a sprawling display of buildings with colorful spires, gardens and waterfalls.
Obama then paid a courtesy call to the ailing, 84-year-old U.S.-born King Bhumibol Adulyadej in his hospital quarters. The king, the longest serving living monarch, was born in Cambridge, Mass., and studied in Europe.
Associated Press writer Jim Kuhnhenn contributed to this report.