The Russian stock market is set to partially reopen after being shut for a month -- the longest break since the collapse of the Soviet Union in 1991. The question is what will the price action actually indicate in a severely restricted market that many consider untestable.

When trading resumes at 9:50 am in Moscow on Thursday [5:50 pm AEDT] for a shortened four-hour session, only 33 stocks will be active, including some of the nation’s biggest companies, such as Gazprom and Sberbank. However, foreigners won’t be allowed to sell equities in a ban scheduled to last until April 1, and short selling won’t be permitted.

“Most of the market was made up of international investors, so the inability for foreigners to sell doesn’t translate into a true market,” said Malcolm Dorson, a money manager at Mirae Asset Global Investments in New York. “Given the country has exited most relevant benchmarks, there could be pressure for forced selling from anyone tracking an index. This first step limits the potential volatility that could come from the first day of trading in multiple weeks.”

Since stocks last traded in Russia on February 25 following its invasion of Ukraine, the country has become a global pariah -- the most sanctioned nation in the world, with a crumbling currency and an expected double-digit output contraction. Add in rampant inflation and even a series of aggressive measures by the government to stabilise local markets may not be enough to overcome selling pressure.

President Vladimir Putin on Wednesday attempted to prop up the sinking rouble by demanding local-currency payments for natural gas purchases from “unfriendly” nations.

“This is a typical example of how to further isolate Russia in a way to improve the local market,” Iskander Lutsko, chief investment strategist at ITI Capital in Moscow, said by phone. “Until we get a resolution on the geopolitics, these kinds of initiatives only make things even worse.”

Charlie Wilson, who manages about $US1.3 billion at Thornburg Investment Management in Santa Fe, New Mexico and held Russian stocks until February, shared a similar view.

Despite Russian regulators’ best efforts, even the limited reopening of the stock market is bound to be chaotic.

“Many investors accessed Russia via UK-listed GDRs [global depositary receipts] and they have all gone to zero,” he said. “There is likely to be some government support for the shares, and I expect trading to be restricted largely to domestic investors that may not have a global perspective about the situation.”