The Chinese central bank and the nation's foreign exchange regulator further eased rules for foreign institutions investing in China's interbank bond market, a measure to further open the financial sector, according to statements released on Wednesday.

Foreign institutions that invest in the interbank bond market directly or under the Qualified Foreign Institutional Investors (QFII) and RMB Qualified Foreign Institutional Investors (RQFII) regimes can transfer its funds in between different accounts , without regular bond trading procedures as before. And the investors only need to register once, said statements on the websites of the People's Bank of China (PBOC) and the State Administration of Foreign Exchange (SAFE).

The new reform measures will further encourage foreign institutional investors to invest in Chinese bond market, promoting financial opening-up, and push forward the internationalization of renminbi, they said.

In the future, PBOC and SAFE will continually study and launch new measures to optimize management and achieve high-quality opening-up in the financial market, according to the statements.

Last month, SAFE removed the QFII and RQFII investment quota restrictions to attract foreign investment.

According to data from China Foreign Exchange Trade System, by the end of June, 1,961 foreign institutional investors have invested in the interbank bond market, and they held about 2 trillion yuan ($281.8 billion) in bonds.

The interbank bond market was introduced by PBOC in 1997, and it is the largest fixed-income market in China, accounting for more than 90 percent of all bond issuance and trading activities. China's $13 trillion bond market exceeded Japan earlier this year and became the world's second largest.