( AP ) - Defense Secretary Robert Gates warned on Friday that Japan and its neighbors must do more to confront security problems in Asia, calling it one of the "last places on earth with the potential for a nuclear confrontation."
It will take more than one or two countries to overcome the threats from North Korea and nuclear proliferation, Gates said in a speech at Sophia University that stressed the United States' continued commitment to Asia yet cautioned that other allies must step up.
" Japan has the opportunity - and an obligation - to take on a role that reflects its political, economic and military capacity," Gates said. "We hope and expect Japan to accept more global security responsibilities in the years ahead."
While Gates did not spell out specific missions Japan should undertake, he offered a few thoughts on that Thursday, saying there are "a number of international peacekeeping and other activities where we believe Japan could play a constructive role."
Speaking in a country well within missile reach of North Korea, Gates used the university speech to caution the Japanese to be mindful that unrest in the Middle East could reach their shores, too.
"As we've learned on more than once occasion, instability or failed states halfway around the world can have serious implications at home," he said. "It is worth remembering that Japan imports 80 percent of its oil from the gulf to power its economy."
Gates' remarks came as Japanese officials remained at odds over Tokyo's recent decision to pull warships from their Indian Ocean refueling mission in support of the U.S.-led coalition operations in Afghanistan. In a pointed reference to that action, Gates said the U.S. alone can't block the flow of weapons to terrorists in the Middle East, which is why partners are needed for security operations and to interrupt shipments.
Japanese Defense Minister Shigeru Ishiba, in a press conference Thursday, referred to ongoing efforts by the government to reach a compromise to resume the refueling mission, saying it is important for Japan's national interests. Speaking through an interpreter, he said "the more the suspension continues, our posture will be deemed as more negative regarding the war on terror."
Senior U.S. defense officials traveling with Gates stressed that this will not be a lobbying mission by Gates to overturn the Japanese decision on the tankers. But he will have lunch later Friday with Japanese officials, including some in the government's main opposition party who are against the Afghanistan mission.
The refueling ships were ordered home after the Japanese government failed to hammer out a compromise over the mission with the main opposition party.
The ships provided about 7 percent of the fuel for maritime patrols, and their loss will trigger more costs and could force ships to refuel on shore, which could put some drain on patrols. The move is not expected to have a major impact on U.S. operations, but the White House said it would like Japan to reconsider.
The threat from North Korea as well as the six-nation talks that have led to the North's initial move this week to begin disabling its nuclear facilities at the main Yongbyon complex have also been key topics during Gates' visit.
Foreign Minister Masahiko Komura said Thursday that he and Gates reaffirmed international efforts to get North Korea to accomplish its obligations to disable its atomic weapons programs.
"In the meantime, Japan and the U.S. will steadily continue our joint missile defense programs," Komura said.
The Japanese have expressed concerns about the possibility that North Korea may eventually be taken off the U.S. list of countries that support terrorism. But on Thursday, Ishiba said he did not seek any specific assurances from Gates that such a decision be delayed.
Gates was scheduled to meet with Prime Minister Yasuo Fukuda and other top government officials during his Tokyo visit.
About 50,000 U.S. troops are based in Japan under a bilateral security treaty.