Updated

In these days of shrinking defense budgets, the U.S. is looking to its southern neighbors to help monitor and protect the Asia Pacific region in the years ahead.

Traveling to Colombia, Brazil and Chile this week, Defense Secretary Leon Panetta underscored the importance of those nations as military partners in a region where the U.S. influence in a number of countries is being challenged by China. And as the military relationships grow, defense officials say it can only help U.S. economic and political ties across the continent.

Panetta's talks with senior defense leaders from the three nations also focused on how the United States can support their military efforts, including those directed at the expanding threat of cyberattacks, according to several senior defense officials who spoke on condition of anonymity because the meetings were private.

U.S. officials left the region thinking that at some point there may be opportunities to talk with South American nations about helping to train Afghan forces after NATO combat troops leave at the end of 2014. Officials would provide no details on which nations might eventually be willing to take on some of the training mission, which will be in need of advisers as other NATO nations pull their troops out.

With the U.S. shifting its focus away from the wars in Iraq and Afghanistan, the Pentagon's new military strategy puts more importance on the Asia Pacific region, where North Korea is a growing threat and China is rapidly building its military and its political and economic influence.

The Pentagon is poised to move more forces to the Pacific region, including plans to rotate units in and out of Australia. The U.S. has long provided training, equipment, assistance and a security umbrella for many of the Asia Pacific nations. With budget cuts looming that will reduce the size of the military, the U.S. is looking to South American countries to be more active global partners.

"The United States, just like other countries, are facing budget constrictions -- which are going to affect the future," Panetta told reporters at a news conference in Brazil. "And what we believe is that the best way to approach the future is to develop partnerships, alliances, to develop relationships with other countries, share information, share assistance, share capabilities, and in that way we can provide greater security for the future."

Panetta would also like to see the South American countries use their greater military capability to train some of the Central American countries that are not as advanced.

All three defense chiefs -- Juan Camillo Pinzon of Colombia, Celso Amorim of Brazil and Andres Allamand of Chile -- brought up cyber threats as a major concern for their countries, including incidents of hacker attacks and data thefts, the U.S. defense officials said as they flew home from Chile, the last stop on the trip.

The three countries, said one of the officials, want help from the U.S. in hardening their computer networks against breaches and increasing their technological skills. The official said there is a recognition of how vulnerable they are, and they want to learn more about the nature of the threat and how to combat it.

That threat, however, is also likely to involve China, which is steadily gaining as a top trading partner and economic developer in South America. It's surpassing the U.S. in trade with Brazil, Chile and Peru, and is a close second in Argentina and Colombia.

For the first time, U.S. intelligence officials publicly called out China late last year as a significant cyber threat. While they did not directly tie attacks to the Beijing government, they said the Chinese are systematically stealing American high-tech data for their own economic gain. The unusually forceful public report seemed to signal a new, more vocal U.S. government campaign against the cyberattacks, which could also involve helping other nations combat similar threats.

The Pentagon's clandestine National Security Agency is an acknowledged world leader in cyber technologies. And U.S. officials have been struggling to work out ways for the government to help other nations as well as the private sector in the United States shore up critical networks.

To date, however, countries around the world have not been able to come up with any detailed agreements on how best to work together. Cyber issues are fraught with legal and political challenges, including conflicting laws and the lack of broadly accepted international guidelines for Internet oversight.

Panetta made it clear as he traveled across the continent that cybersecurity was "a whole new arena" that all the nations are concerned about. He also encouraged the South American nations to expand their security efforts to other regions, including Africa.

"The United States must remain a global power," Panetta said during a speech in Brazil. "But ... more and more nations are making and must make an important contribution to global security. We welcome and encourage this new reality because frankly it makes the world safer and all of our nations stronger."