As Russia prepares to allow traders from “friendly” countries which have not sanctioned the nation to trade on the Moscow Exchange, the Russian central bank announced steps Monday which will prevent investors from “unfriendly” countries  from taking advantage of those plans, to offload stocks they could otherwise not sell.

After an almost six-month hiatus, the Moscow exchange announced plans to allow clients from “friendly” countries, namely those which have not sanctioned Russia following its invasion of Ukraine, to resume trading stocks on their market.

However it later limited this move to just the derivatives market, and did not make any statement as to when that would be expanded into wider access to the regular market.

Analysts said the delay was over concerns that investors based out of the European Union, United States and Britain might be able to use that access from friendly countries as a back-door to offload any Russian stocks they still hold.

On Monday the central bank said Russian depositories and registrars would be blocked for six months from executing transactions with securities from foreign counterparts, including friendly countries.

The regulator noted there had been cases where brokers were offering the option of purchasing securities from non-residents in foreign countries, and then transferring them into a Russian depository. It labeled such schemes as “risky” and noted there was, “no guarantee of obtaining the expected financial result.”

In the aftermath of the Ukraine conflict, Western sanctions have limited Russian’s access to global stock markets, while Russian countermeasures have blocked foreigners from trading in Russian shares.