Workers clean a train car at a maintenance plant for the Kunming Metro, in Kunming, Yunnan province, April 13, 2016. REUTERS/Brenda Goh

SHANGHAI (Reuters) - China’s investment in metro systems is expected to hit more than 1 trillion yuan ($148.28 billion) by 2020, as government planners accelerate approvals for such projects, the state-owned Economic Information Daily reported on Friday.

Since September, Beijing has approved more than 100 billion yuan worth of urban rail transit projects in the cities of Baotou, Urumqi and Xiamen, the newspaper said, adding that other localities were speeding up construction.

About 40 Chinese cities are currently building metro systems and 60 are designing and making plans, according to the China Association of Metros.

The newspaper said that, however, there has been growing concern over such projects’ financing models as they tend to bring in low income but require large amounts of investment, and that the National Development and Reform Commission was encouraging governments to attract private funding.