* Obama seeking to underline U.S. commitment to region
* U.S. needs to balance Japanese and Chinese concerns (Adds Japanese media reports that joint statement likely to say disputed islands covered by mutual security tready)
By Linda Sieg and Matt Spetalnick
TOKYO, April 24 (Reuters) - President Barack Obama will use a state visit to Japan on Thursday to try to reassure Tokyo and other Asian allies of his commitment to ramping up U.S. engagement in the region, despite Chinese complaints that Washington's real aim is to contain Beijing's rise.
Obama will be treated to a display of pomp and ceremony meant to show that the U.S.-Japan alliance, the main pillar of America's security strategy in Asia, remains solid at a time of rising tensions over growing Chinese assertiveness and North Korean nuclear threats.
It was unclear, however, whether a last-ditch round of talks between U.S. and Japanese negotiators would yield a breakthrough on a two-way trade pact seen as crucial to a broader trans-Pacific agreement that Obama has championed.
The challenge for Obama during his week-long, four-nation tour will be to convince Asian partners that Washington is serious about its promised strategic "pivot" towards the region, while at the same time not harming U.S. ties with China, the world's second-biggest economy.
The difficulty of Obama's balancing act was underscored hours before he arrived on Wednesday night when Chinese state media criticized U.S. policy in the region as "a carefully calculated scheme to cage the rapidly developing Asian giant".
Obama told Japan's Yomiuri newspaper that while Washington welcomed China's peaceful rise, "our engagement with China does not and will not come at the expense of Japan or any other ally."
Obama's trip will also include stops in South Korea, Malaysia and the Philippines and leaders who will meet Obama are also keeping a wary eye on the crisis in Ukraine through the prism of their own territorial disputes with Beijing
Some of China's neighbors worry that Obama's apparent inability to rein in Russia, which annexed Crimea last month, could send a message of weakness to China.
TRADE GAPS OR PROGRESS?
The eve of Obama's arrival in Japan was marked by a final push by U.S. and Japanese negotiators for a trade deal to support the broader Trans-Pacific Partnership (TPP), which would connect a dozen Asia-Pacific economies.
Even if a U.S.-Japan pact cannot be finalized before Obama leaves Tokyo on Friday, Obama and Japanese Prime Minister Shinzo Abe are likely to try to project a sense of progress on key issues. Gaps remained over Japan's agriculture and both sides' auto markets.
The Japanese government lobbied hard to get the White House to agree to an official state visit, the first by a sitting U.S. president since Bill Clinton in 1996.
Thousands of ordinary Japanese lined the street in downtown Tokyo on Wednesday evening, hoping to glimpse Obama as he headed for dinner with Abe at a sushi restaurant after his arrival.
Obama lauded the fare after his meal with Abe. "That's some good sushi right there," he said as he and the Japanese leader left Sukiyabashi Jiro, a venerable establishment in Tokyo's bustling Ginza shopping district run by an octogenarian chef.
Topping Obama's schedule on Thursday will be an audience with Emperor Akihito at the Imperial Palace and a summit with Abe followed by a joint news conference. He will also visit the Meiji Shrine, which honors a Japanese emperor who died in 1912, and attend a state banquet in the president's honor.
Abe will be trying to soothe U.S. concerns that his conservative push to recast Japan's war record with a less apologetic tone is overshadowing his pragmatic policies on the economy and security.
Obama and Abe are expected to send a message of solidarity after strains following Abe's December visit to Tokyo's Yasukuni Shrine, seen by critics as a symbol of Japan's past militarism.
In his remarks to the Japanese newspaper, Obama assured Japan that tiny isles in the East China Sea at the heart of a territorial row with China are covered by a bilateral security treaty that obligates America to come to Japan's defence.
That is long-stated U.S. policy, but the confirmation by the president will be welcome in Japan.
A joint statement to be issued at the summit will state the two allies will not tolerate any attempt to change the status quo by force, a phrase that implicitly targets China. Japanese media reported on Thursday that the statement was likely to specifically mention that the disputed islands fall under the U.S.-Japan security treaty.
Calling Washington's policy "myopic", Chinese state news agency Xinhua said: "The United States should reappraise its anachronistic hegemonic alliance system and stop pampering its chums like Japan and the Philippines that have been igniting regional tensions with provocative moves."
Previewing Obama's Asia tour, his national security adviser, Susan Rice, rejected the notion that China was being targeted.
"With respect to the trip and whether it ought to be viewed as a containment of China, I would say this trip has a very positive, affirmative agenda," she told reporters. (Additional reporting by Mark Felsenthal, Antoni Slodkowski and Chris Meyers; Editing by Mike Collett-White)