Russian President Vladimir Putin has signed a decree to protect the interests of strategic Russian companies operating abroad.
The decree has come within days of the launch of an EU probe into whether Russian energy company Gazprom is abusing its dominant position in central and eastern Europe.
Firms will be required to get government permission before disclosing information to foreign regulators. They will also need official approval before changing contracts or selling property abroad.
Putin has ruled out a trade war over the investigation which centres on Gazprom’s policy of linking contract gas prices to oil prices.
The Kremlin said it will not reduce gas supplies to Europe in retaliation for the probe.