China and the U.S. opened a joint nuclear safety center in Beijing Friday intended to offer training on the safe handling of nuclear materials and the prevention of terrorist attacks on nuclear facilities.

U.S. Energy Secretary Ernest Moniz and the head of China's nuclear agency, Xu Dazhe attended the opening ceremony.

Moniz credited the Chinese for working with the U.S. and taking important steps towards nuclear safety. But he raised concerns about China's plans to process nuclear waste into plutonium that could be used to make nuclear weapons.

"China is taking very very strong steps and this center of excellence is in some sense the exclamation point to show that commitment," Moniz said. "With regard to plutonium recycling well we've expressed our concern globally in terms of separating plutonium and we question the economics quite frankly, but what we think is very important that when countries are doing this and again we've expressed this in terms of other countries is that it's very important that build-up of separated plutonium is not part of the process."

China maintains that the plutonium reprocessing would be only for commercial purposes.

China's Atomic energy authority chief Xu said the center showed China's commitment to furthering nuclear safety and represents progress in China's nuclear safety technology levels.

Moniz told the Associated Press news service that he would like to see China play a bigger role in regional and world nuclear security.

China's president, Xi Jinping, and U.S. President Barack Obama are set to meet in Washington this month for a summit on nuclear security.