China failed to attain its planned targets for slashing energy consumption and carbon emissions in 2011, highlighting the urgency of stepping up the country's economic structural shift, the head of the top economic planning agency said on Monday.

The country missed about half of its major targets for energy conservation and environmental protection in 2011, Zhang Ping, minister of the National Development and Reform Commission (NDRC), told journalists on the opening day of the Fifth Session of the 11th National People's Congress.

"There are a couple of complicated reasons for failing to meet the targets. The biggest is that we have not transformed the economic development model," he said.