Investing.com -- The United States may allow production of Lockheed Martin's PAC-3 Patriot missiles outside American borders, according to U.S. Undersecretary of Defense Michael Duffy.

Duffy made the statement at a defense industry gathering on the sidelines of the NATO summit in Ankara. When asked whether PAC-3 production could take place outside the United States, he said the country remains open to such possibilities.

"We leave open the opportunity for production beyond the U.S. borders, absolutely," Duffy said.

The PAC-3 represents an advanced version of the Patriot missile system manufactured by Lockheed Martin.