Russia’s budget surplus for 2022 has almost evaporated after a sharp drop in energy exports during August led to a monthly deficit of as much as Rbs360bn ($5.9bn).

Russia recorded a surplus of almost Rbs500bn in the first seven months of the year. But the cumulative total fell to only Rbs137bn last month, suggesting a big deficit in August which economists attributed to sharp declines in oil and gas revenues. Russia’s surplus over the first six months of the year reached Rbs1.37tn as it built a war chest on the back of soaring energy prices.

Russian gas flows to Europe have dwindled to about one-fifth of pre-invasion deliveries. In early September it said it would keep Nord Stream 1, which runs under the Baltic Sea to Germany, shut indefinitely unless the west lifted sanctions imposed over Moscow’s invasion of Ukraine.