BEIJING -- China's commercial banks saw a net forex settlement surplus of 26.9 billion yuan (about $4 billion) in September, the country's forex regulator said on Friday.

Forex purchases by banks stood at over 1.23 trillion yuan last month, while sales came in at almost 1.21 trillion yuan, data from the State Administration of Foreign Exchange (SAFE) showed.

In the first nine months, forex purchases by banks totaled just under 10.25 trillion yuan, while sales topped 9.71 trillion yuan, with a net forex settlement surplus of 535.7 billion yuan.

The country's forex market was generally stable in the first three quarters with balanced supply and demand, said Wang Chunying, deputy director and spokesperson of SAFE, noting that the effective containment of COVID-19 and economic recovery had offered strong support for market stability.

China is forming a new development pattern known as "dual circulation," which takes the domestic market as the mainstay while allowing domestic and foreign markets to boost each other, and the new pattern will boost high-level opening-up and further improve the quality of two-way cross-border investment, Wang said.