Power of Chinese yuan grows.

SHANGHAI : Whenever the Japanese yen wavers, Asian central bankers turn a nervous eye to China's tightly guarded yuan currency, hoping the People's Bank will stand firm and protect regional exchange rate stability.

But despite China's swelling economic clout and its currency's growing importance and usage in Asia, Beijing has to lift rigid capital controls before the yuan can dream of carrying the international weight of its neighbour's yen, analysts said.

The yuan is carving a deeper presence in Asia, especially in Southeast Asia and Indochina as booming trade and tourism boost non-official usage of the currency, also called the renminbi.

It is interchangeable in trade fairs and markets near the Chinese border in northern Vietnam, Laos and Myanmar, sometimes even more acceptable than the US dollar.

Tourist shops in Hong Kong, …