Finance regulators in South Korea are reportedly looking to cooperate with authorities in China and Japan on new rules for cryptocurrency trading.

A Jan. 8 report by Yonhap News states that representatives from the Korean Financial Services Commission (FSC), as well as those from the relevant agencies in Japan and China, met last month to discuss the oversight of cryptocurrency investment.

FSC chairman Choi Jong-ku, according to the source, told reporters that the countries plan to cooperate in their efforts to curb speculative investing. Jong-ku reportedly called investing in cryptocurrencies “irrational,” going on to say:

“[A] fever of speculative investment in cryptocurrencies is ongoing … however, cryptocurrencies are unable to play a role as a means of payment.”

The report follows a statement by the country’s Financial Supervisory Service (FSS) and Financial Intelligence Unit, which outlined how the two bodies have begun inspecting six banks to ensure they are in compliance with newly-implemented anti-money laundering regulations.

The banks in question have ties to the country’s bitcoin exchange ecosystem, which in recent months has seen elevated trading volumes and prices trading at high premiums compared to other marketplaces around the world. South Korean officials have expressed concern about price speculation around cryptocurrencies in the past.

And in what is perhaps a sign of the speculative boom taking place in the country, data site CoinMarketCap excluded three Korean exchanges earlier this week due to the price differences.

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