The Chinese yuan's recoil from a near four-year high has raised market nerves that a recent period of stability is ending, which could leave regional peers exposed especially as U.S. interest rates start to rise.

A steady yuan, along with robust exports and currency reserves, has helped shield Asia's emerging markets from the sort of exodus typically seen when developed market interest rates rise.

Yet slowing economic momentum and policy easing in China, amid expectations for as many as seven U.S. rate hikes this year, has cast a pall over the yuan outlook, historically an ill wind for neighbors.