Nomura Asset Management said on Friday it will suspend new subscriptions of a popular U.S. REIT investment trust fund as heavy inflows from retail investors boosted its size beyond the appropriate level to manage the fund.

Japan's top asset management company was forced to suspend the offering after the value of the fund nearly tripled to 275 billion yen ($3.1 billion) almost a month after its launch.

The fund that invests in North American REITs also allows investors to select a currency which they want to hold the fund, such as the Brazilian real.

Such currency-selective type investment trust funds or toushins have been attracting strong demand from the start of the year, and were pioneered by Nomura Asset in January.

The latest suspension was the third one by Nomura Asset after halting the subscription of two series of currency-select U.S. junk bond funds.

Japanese individuals hold about $15 trillion in personal savings largely parked in low-yielding accounts and retail investors have been taking on more risk as the global economy picks up and while the Tokyo stock market lags other markets.

The overall value of toushins hit a 13-month high above 60 trillion yen in October as retail investors poured money in the REIT funds and into emerging markets, mainly in Brazil, Japan's Investment Trusts Association said.

($1=88.83 yen)

(Reporting by Chikafumi Hodo; Editing by Edwina Gibbs)