Gas markets swung sharply on Wednesday after Russia’s president Vladimir Putin said his country was prepared to stabilise the soaring global energy prices that are threatening to curb industrial activity and sharply raise inflation.

UK and European natural gas prices shot higher early in the day to trade at close to 10 times their level from the beginning of the year. But prices abruptly reversed course hours later when Putin hinted that Russia’s state-backed monopoly pipeline exporter, Gazprom, may increase supplies to help Europe avoid a full-blown energy crisis.

“Let’s think through possibly increasing supply in the market, only we need to do it carefully. Settle with Gazprom and talk it over,” Putin said. “This speculative craze doesn’t do us any good.”

Gas traders say one of the drivers of the rally in prices is that Russia is limiting its European gas supplies to the levels in long-term contracts, and has let Gazprom’s storage facilities in the continent fall to very low levels.

Putin said Gazprom was exceeding its contractual obligations for gas supplies through Ukraine this year.

His remarks appeared aimed at staving off criticism from Europe that Russia is holding back supplies as it awaits approval for the controversial new Nord Stream 2 pipeline, which bypasses Ukraine to send gas to Germany. That project edged closer to going live on Wednesday after a judicial opinion in the EU.

UK gas contracts for November delivery surged almost 40 percent as trading opened to reach more than 24 per therm, having started the year below 50P. But after Putin’s intervention, they ended the day down 9 percent, at 22.71.

The gas industry was shaken by the swings in the price. Tom Marzec-Manser at ICIS, a consultancy, said it was “the most volatile and unpredictable day that many in the industry will ever witness”.