The International Energy Agency has called on Russia to send more gas to Europe to help alleviate the energy crisis, becoming the first major international body to address claims by traders and foreign officials that Moscow has restricted supplies.

The Paris-based group said that while Russia was fulfilling long-term contracts to European customers it was supplying less gas to Europe than before the coronavirus pandemic.

“The IEA believes that Russia could do more to increase gas availability to Europe and ensure storage is filled to adequate levels in preparation for the coming winter heating season,” said the IEA, which is primarily funded by OECD members to advise on energy policy and security.

“This is also an opportunity for Russia to underscore its credentials as a reliable supplier to the European market. ”

Some European members of parliament have called for an investigation into Gazprom, Russia’s state-backed monopoly exporter of pipeline gas. Foreign officials and traders have questioned why the company has limited top-up sales in the spot market to Europe, saying that this has fuelled a surge in prices that is raising household bills and threatening industries across the continent.

The company has also unsettled energy traders by keeping the underground storage facilities it controls in Europe stocked at low levels compared with previous years.

Gazprom’s chief executive Alexei Miller last week said the company was meeting its supply obligations and was ready to increase production if needed. But he warned prices could rise further in the winter because of shortages in underground facilities.

Gas prices rose again on Monday after Gazprom declined to book additional capacity for export via Ukraine for October and reserved only one-third of the available space on the Yamal gas pipeline via Poland.

Russia also wants to gain approval to start the Nord Stream 2 pipeline to Germany, a recently completed project that is contentious partly because it will redirect some of the gas that flows through Ukraine, where Russia has waged a proxy war in eastern border regions since 2014.

Gazprom and Kremlin officials have said Russia could boost gas sales once Germany and the EU approve the start-up of the pipeline, adding to suspicions that it has restricted sales in order to try to accelerate the decision.

The ILA, which was formed after the Arab oil embargoes of the 1970s, did not solely blame Russia for the rise in prices. It said strong demand for liquefied natural gas in Asia, which has diverted cargoes from Europe, had tightened supplies globally.

It added that blaming the rise of renewable energy for the price surge was misguided. Lower wind speeds in Europe this summer are one factor that has boosted demand for gas.

“Recent increases in global natural gas prices are the result of multiple factors, and it is inaccurate and misleading to lay the responsibility at the door of the clean energy transition,” the IEA said.

Thierry Bros, a former oil and gas adviser at the French economy ministry and a professor at Sciences PO in Paris, said the IEA was “highlighting what has been discussed in the industry for some time but many politicians in Europe have been hesitant to address — the role Russia has played in the current energy crisis”.

“In many ways this is the IEA returning to what it was originally set up to do — ensuring security of supply. ”