By Linda Sieg
TOKYO (Reuters) - Japan will be seeking clues to Washington's policies on a volatile North Korea and a rising China while hoping to steer clear of trade rows when U.S. Secretary of State Rex Tillerson meets officials on Thursday at the start of his first Asia trip.
The former oil executive, who will also travel to South Korea and China, will seek to reassure Tokyo and Seoul about countering North Korea's growing nuclear prowess, and press China to do more on one of the most serious security threats facing President Donald Trump.
Tillerson is expected to confirm the "unshakeable bond" of the U.S.-Japan alliance and underline cooperation on meeting the threat from Pyongyang's missile and nuclear programmes when he meets Foreign Minister Fumio Kishida and Prime Minister Shinzo Abe. Abe is the only Asian leader to have met U.S. President Donald Trump since his inauguration, and Trump said the United States was "100 percent" behind Japan.
North Korea last week launched four more ballistic missiles and is working to develop nuclear-tipped missiles that can reach the United States.
Tillerson will have "substantive, hard" talks with U.S. partners in Asia on next steps in dealing with North Korea, but his visit is not likely to produce an immediate specific response, the State Department said on Wednesday.
Washington has previously said all options, including military, are on the table in its review of policies toward North Korea and Japanese officials are keen to know more details.
U.S. Defence Secretary Jim "Mattis correctly said all options are on the table ... but as a practical matter, I don't see the administration deciding to preemptively strike North Korea's capabilities," said Michael Green, a former U.S. official now at the Center for Strategic and International Studies in Washington.
Japan has a pacifist constitution but influential lawmakers have been pushing for the country to develop the ability to counter Pyongyang's military advances.
Tokyo is also considering beefing up its ballistic missile defences with a U.S. Terminal High Altitude Area Defense (THAAD) anti-missile system or Aegis Ashore, a land-based version of the missile defence system used at sea.
China's assertiveness in the East China Sea, where it has a territorial row with Japan, and the South China Sea, where it has disputes with the Philippines and several other Southeast Asia nations, will also be on the agenda as will trade.
Trump administration trade adviser Peter Navarro cited Japan on Monday for non-tariff trade barriers and said Washington must use its leverage as the world's largest market to boost U.S. exports.
Some Japanese officials, though, say trade will take a back seat to security. "We have more key issues of common concern, like North Korea," one official said, declining to be identified because he was not authorised to speak to media.
(Additional reporting by Kiyoshi Takenaka in Tokyo and David Brunnstrom in Washington; Editing by Raju Gopalakrishnan)