LONDON (AP) — Russian shares slumped as its stock market resumed trading of all companies Monday after a monthlong halt following the invasion of Ukraine.

The benchmark MOEX index slid 2.2% after the Moscow Exchange reopened for all of its several hundred listed companies, but with restrictions still in place to limit volatility. State-owned energy giant Gazprom fell 3.7%, while airline Aeroflot was up 3%.

The last full trading session in Moscow was on Feb. 25, a day after the index tumbled by a third after President Vladimir Putin ordered the invasion of Ukraine.

Prices whipsawed last week when the exchange tentatively reopened for two days of limited trading, with investors allowed to trade only 33 of the MOEX index's 50 companies.

Some restrictions remained in place Monday to prevent another big selloff, including the daily session shortened to four hours and a ban on short-selling, which essentially involves betting on stock prices to go down.

Foreigners also are unable to sell shares until Friday — a restriction Russia put in place to counter Western sanctions against its financial system and the ruble, which has been sharply devalued.

Foreign investors are scrambling to figure out how to cut their Russian holdings in light of the sanctions. Investment analytics company MSCI removed the country from its emerging markets indexes, which are widely followed by fund managers, and dubbed the country's stock market “uninvestable.”

Moscow’s stock exchange is tiny compared with other major ones like the New York Stock Exchange.