Reported by Georgi Kantchev and Evan Gershkovich

An oil refinery next to the frozen Irtysh River in the Siberian city of Omsk. ALEXEY MALGAVKO/REUTERS

MOSCOW—The opening months of Russia’s invasion of Ukraine last year drove an increase in oil and natural-gas prices that brought a windfall for Moscow. Those days are over.

As the war continues into its second year and Western sanctions bite harder, Russia’s government revenue is being squeezed and its economy has shifted to a lower-growth trajectory, likely for the long term.

The country’s biggest exports, gas and oil, have lost major customers. Government finances are strained. The ruble is down over 20% since November against the dollar. The labor force has shrunk as young people are sent to the front or flee the country over fears of being drafted. Uncertainty has curbed business investment.

“Russia’s economy is entering a long-term regression,” predicted Alexandra Prokopenko, a former Russian Central Bank official who left the country shortly after the invasion.

There is no sign the economic difficulties are bad enough to pose a short-term threat to Russia’s ability to wage war. But state revenue shortfalls suggest an intensifying dilemma over how to reconcile ballooning military expenditures with the subsidies and social spending that have helped President Vladimir Putin shield civilians from hardship.

Russian billionaire Oleg Deripaska warned this month that Russia is running out of cash. “There will be no money next year, we need foreign investors,” the raw-materials magnate said at an economic conference.

Having largely lost its European market next door, and with other Western investors pulling out, Moscow is becoming ever more reliant on China, threatening to realize long-simmering fears in Moscow of becoming an economic colony of its dominant southern neighbor.

“Despite Russia’s resilience in the short term, the long-term picture is bleak: Moscow will be much more inward-looking and overly dependent on China,” said Maria Shagina, a senior fellow at the International Institute for Strategic Studies think tank in London.

A big part of the dimming outlook stems from a bad bet by Mr. Putin last year that he could use Russian energy supplies to limit Western Europe’s support for Ukraine.

European governments, instead of tempering their support for Kyiv, moved rapidly to find new sources of natural gas and oil. Most Russian gas flows to Europe stopped, and after an initial jump, global gas prices fell sharply. Moscow now says it will cut its oil production by 5% until June from its previous level. It is selling its oil at a discount to global prices.

As a result, the government’s energy revenue fell by nearly half in the first two months of this year compared with last year, while the budget deficit deepened. The fiscal gap hit $34 billion in those first two months, the equivalent of more than 1.5% of the country’s total economic output. That is forcing Moscow to dip deeper into its sovereign-wealth fund, one of its main anti-crisis buffers.

Read full report: https://www.wsj.com/articles/russias-economy-is-starting-to-come-undone-431a2878?mod=world_lead_story