MANILA, Philippines (AP) — The Asian Development Bank's chief says trade in Asia, growing at a fast clip since 2017, could be disrupted if disputes escalate.

Asked about trade friction between the U.S. and China, ADB President Takehiko Nakao said Thursday that so far mounting friction has not measurably hurt that activity. But the possibility disputes might escalate is a concern, since Asia's strong growth is based on open trade and investment.

Nakao was speaking to reporters at the outset of the ADB's annual meeting, being held in Manila, Philippines. Asked about China's "Belt and Road Initiative," he said developing countries need to take a careful look at projects backed by the program and avoid taking on unsustainable debt.

He said infrastructure projects must be economically sound so countries can repay loans.