Russia's Energy Ministry is limiting access to its statistics on oil and gas production and exports, it said on 14 April.
The ministry "is limiting the distribution of information, which could be used as an additional pressure on the Russian market and its participants," it said.
The ministry unit that compiles the data, the CDU TEK, did not publish monthly data on 2 April, according to two clients, in the first such delay in years.
Russia has faced Western sanctions since the start of what Moscow calls its "special military operation" in Ukraine on 24 February.
"The industry's statistical data, amid the restrictions, is quite sensitive to manipulation, which endangers operations of CDU TEK's counterparties," the ministry said.