China's 857 billion yuan (US$132.25 billion) national pension fund is seeking more overseas institutions to manage its offshore investments, it said in a statement on its website on Thursday.

The fund seeks candidate firms that have at least six years of experience in managing not less than US$5 billion worth of assets.

The aspiring firms are also required to have a clean record and have not been punished by industry supervisors.

The money entrusted by the fund will be used to buy multi-asset allocation products, local currency debt products in emerging markets, excluding China, global natural resources equity products and global real estate equity products.

Selection of the hopeful firms will be done in four stages, including application submissions and face-to-face interviews, the statement said.

This is the third time the fund has sought foreign asset managers.

Since 2006 it has picked nine overseas managers, including Allianz, INVESCO, a UBS and China International Capital Corp joint investment team, AXA Rosenberg, State Street Global Advisors and BlackRock, according to its website.

Total assets of the fund have increased nearly 10 times over the past decade to almost 857 billion yuan. The fund achieved an average investment yield rate of 9.17 percent during the period.