Visiting US President Barack Obama said?in?Shanghai on?Monday that Shanghai and Chicago can learn from each other especially on clean energy.

He made the remarks during a dialogue with Chinese students at the Shanghai Science and Technology Museum. It is his first trip to China since taking office in January.

"It's a terrific opportunity for us to learn from each other," he said.

"In the United States we are learning how to develop buildings that use much less energy and that are much more energy-efficient. I noticed in Shanghai many new buildings are growing up. It's important to incorporate these new technologies so that each building is energy-efficient when it comes to lighting, when it comes to heating," he said.

Clean energy issue is going to be a major focus in the 2010 Shanghai World Expo, he said.

Shanghai and Chicago have been sister cities since 1985.