WASHINGTON -- US alliances with South Korea and Japan are the key to addressing most pressing issues in the Indo-Pacific region that include China's aggression and North Korea's nuclear programs, top US officials said, calling the alliances force multipliers.

US Secretary of State Antony Blinken and Defense Secretary Lloyd Austin also said the US will continue to address such issues diplomatically but also maintain the world's most powerful military to support its efforts.

"Our alliances are what our military calls 'force multipliers.' We're able to achieve far more with them than we could without them," they said in a joint opinion piece published Monday by US daily the Washington Post.

"It would be a huge strategic error to neglect these relationships. And it's a wise use of our time and resources to adapt and renew them, to ensure they're as strong and effective as they can be," they added about their upcoming trip to Japan and South Korea.

Blinken arrived in Tokyo earlier in the day for talks with his Japanese counterparts in bilateral and two-plus-two meetings that will also involve the top defense chiefs of the countries.

He and Austin are due in Seoul on Wednesday (Seoul time) for talks with their South Korean counterparts.

"Our work with Japan and South Korea covers a vast range of issues that are critical to our security and prosperity -- and to the world's. Our diplomats and defense leaders strategize together on how to confront shared threats such as North Korea's nuclear weapons and ballistic missile programs," they wrote.

The US secretaries said the US and the two Asian allies are working together on a wide range of regional and global issues such as climate change, cybersecurity and pandemic preparedness, but hinted that China will be a major topic of their discussions.

"Some seek to challenge the international order -- that is, the rules, values and institutions that reduce conflict and make cooperation possible among nations. As countries in the region and beyond know, China in particular is all too willing to use coercion to get its way," they said.

"Our combined power makes us stronger when we must push back against China's aggression and threats. Together, we will hold China accountable when it abuses human rights in Xinjiang and Tibet, systematically erodes autonomy in Hong Kong, undercuts democracy in Taiwan or asserts maritime claims in the South China Sea that violate international law," they added.

The secretaries said the US will seek diplomatic solutions to the problems facing the US and its allies in the Indo-Pacific region, "because it's the most effective way to meet the challenges we face today, few of which can be solved by us acting alone."

"At the same time, we will maintain the world's most powerful armed forces, because that's a core source of our national -- and collective -- strength." (Yonhap)