In these days of shrinking U.S. defense budgets, the Obama administration is looking to South America to help monitor and protect the Asia-Pacific region in the years ahead.

During visits to Colombia, Brazil and Chile this past week, Pentagon chief Leon Panetta underscored their importance as military partners in the Pacific, where China is challenging U.S. influence in a number of countries. As those defense relationships grow, officials say it can only help U.S. economic and political ties across South America.

Panetta's talks 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 countries might eventually be willing to take on some of the training mission, which will need advisers as other NATO nations withdraw their troops.

With the U.S. turning its focus from Iraq and Afghanistan, the Pentagon's new military strategy puts more importance on the Asia-Pacific region. North Korea is a growing threat while China is building its military and working to expand its political and economic influence.

The Pentagon is poised to move more forces to the Pacific, including rotating units in and out of Australia. The U.S. has long provided training, equipment, assistance and a security umbrella for many of the region. With looming budget cuts 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 like to see South American countries use their greater military capability to train some Central American nations that are not as advanced.

Defense chiefs Juan Carlos Pinzon of Colombia, Celso Amorim of Brazil and Andres Allamand of Chile brought up cyberthreats as a major concern, including incidents of hacker attacks and data thefts, U.S. defense officials said.

The three countries, said one official said, 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 is 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 cyberthreat. 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.

The Pentagon's clandestine National Security Agency is an acknowledged world leader in cybertechnologies. U.S. officials have struggled 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 come up with any detailed agreements on how best to work together. These issues present legal and political challenges, including conflicting laws and the lack of broadly accepted international guidelines for Internet oversight.

Panetta made it clear that cybersecurity was "a whole new arena" that all the nations are concerned about. He also encouraged 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."