Investors are optimistic of a relatively stable renminbi in the long run amid easing pressure from capital outflows, according to China's top currency trade regulator.

Data from the State Administration of Foreign Exchange shows that the deficit from the buying and selling of foreign-currency forwards by Chinese banks shrank from $54.4 billion in January to $12.5 billion in May.

"The pressure of capital outflows has eased, and the deficit in the selling and buying of Chinese banks continues to shrink. For the first time in 17 months, China's banks bought more foreign-currency forwards than they sold," said Xie Yaxuan, chief economist with China Merchants Securities Company.