The Chinese yuan is on course to become a much more influential part of the global financial system with almost a third of central banks planning to add the currency to their reserve assets, a closely followed survey showed on Wednesday.

The Global Public Investor survey, published annually by the London-based OMFIF think tank, showed 30 percent of central banks plan to increase yuan holdings over the next 12-24 months, compared with just 10 percent last year.

The yuan's rise will almost certainly be a global trend, but may be especially strong in Africa where almost half of central banks are planning to increase their yuan reserves.

In stark contrast to the yuan, 20 percent of central banks plan to reduce their holdings of the U.S. dollar over the next 12-24 months and 18 percent plan to reduce their euro holdings.

In their search for yield, close to 30 percent of global public investors – central banks, sovereign wealth funds and public pension funds – will reduce their exposure to developed market sovereign bonds, while more than 20 percent plan to buy more emerging market government debt.

Global public investors are also increasing demand for sustainable assets and becoming more active investors. Some 92 percent of central banks invest in green bonds and 21 percent in sustainable equities. Around 65 percent of central banks plan to add to their green bond holdings, up from 45 percent last year.

One in 10 central banks also said that sustainability was now their joint-most important institutional priority, although half still did not explicitly implement environmental, social and governance considerations in their portfolios.

(With input from Reuters)