In Japan, the world’s largest leveraged exchange traded fund is growing too large to control.

Nomura Asset Management Co. will halt subscription orders for its Next Funds Nikkei 225 Leveraged Index ETF, along with two other funds, from Friday, stating that underlying liquidity is not deep enough to ensure the leveraged products can meet their target strategy, Bloomberg reports.

“It seems that the ETF has become too big and is moving the market, and that they’re unable to secure the liquidity they need,” Michiro Naito, an equity derivatives and quantitative strategist at JPMorgan Securities Japan Co., told Bloomberg.

Next Funds Nikkei 225 Leveraged Index ETF tries to generate two times the multiple of the Nikkei 225 Index. The leveraged ETF has gathered ¥733.6 billion, or $6.2 billion, in assets under management with an average daily volume of 10.9 million shares, according to Morningstar. In contrast, the largest U.S.-listed leveraged ETF is the ProShares UltraShort 20+ Year Treasury (NYSEArca: TBT) with $2.7 billion in assets under management.

The Next Funds Nikkei 225 Leveraged Index ETF has become a popular way among Japanese investors to squeeze returns, attracting a surge of inflows, which has also made the leveraged ETF the largest player in Japan’s futures market. Assets under management have doubled in just five months even while the underlying benchmark flopped 13% from the June peak.