BEIJING -- China's top economic planner approved seven fixed-asset investment projects with their combined investment totaling 129.8 billion yuan ($18.35 billion) in May, an official said Tuesday.

The projects were mainly in the transportation and energy sectors, Meng Wei, spokesperson with the National Development and Reform Commission, told a press conference.

Next, the commission will accelerate the implementation of investment plans within the central budget in a bid to scale up effective investment, Meng said.

Fixed-asset investment includes spending in infrastructure, property, machinery and other physical assets.

Official data showed that China's fixed-asset investment declined 6.3 percent year on year to 19.92 trillion yuan in the first five months, narrowing by 4 percentage points from that in the January-April period.