Two sources confirmed the information to Reuters, amid fears of an imminent total suspension of Russian gas supplies.
Gazprom is expected to restart gas flows through the Nord Stream 1 pipeline Thursday, after the completion of a 10-day maintenance that has put EU leaders on edge.
Two sources familiar with the plans confirmed the information to Reuters.
Gas flows are set to resume on Thursday but will not match the usual capacity of 160 million cubic metres (mcm) per day, the sources told the news agency.
During a trip to Teheran, Russian President Vladimir Putin said Gazprom has fulfilled and will fulfil its obligations "in full," even if the company has already reduced supplies to several European countries.
Russia is propping up its currency, the rouble, and its public coffers thanks to soaring gas prices.
The news offers some relief to European governments who have been preparing in case the Kremlin uses the maintenance to indefinitely cut off gas supplies in retaliation for the Western sanctions imposed since the start of the Ukraine war.
The fears were further fuelled by a recent dispute around a gas turbine that Canada decided to ship back to Germany under a "time-limited and revocable" permit.
Gazprom claimed the turbine was essential for the functioning of Nord Stream 1, but Ukraine blasted Canada's decision as a show of weakness. By contrast, the EU and the US welcomed the move.
The turbine's whereabouts are unclear.
Kommersant, a Russian newspaper, reported Canada sent the equipment by plane on 17 July.
"It is difficult to say whether Nord Stream 1 will run after ten days of maintenance. The past has often shown that technical reasons are often excuses for political decisions. Of course, this could happen again," Robert Habeck, Germany's vice-chancellor, said earlier this month.
"Nobody can see inside Putin's head, so we do not know what will happen."
Gazprom, a state-controlled multinational that enjoys exclusive rights on the exports of Russia gas pipeline, has already reduced flows to several EU countries, including Germany, France and Italy.
In some cases, it has completely interrupted the supplies.
Last week, the company began a planned 10-day operation maintenance across Nord Steam 1, leading to a halting of gas flows. The operation was scheduled to conclude on 21 July.
Gazprom also informed some customers it could not fulfil its contractual obligations due to force majeure or unavoidable circumstances.
Nord Stream 1 is a massive underwater pipeline that physically connects Russia with Germany, accounting for more than a third of Russian gas exports to the EU.
The bloc is scrambling to fill its gas storage ahead of the winter season in a bid to avert rationing and industrial shutdowns.
In its latest economic forecast, the European Commission admitted that a total interruption of Russian gas would trigger a recession in the second half of the year and continue to depress growth in 2023.
"In light of recent events, this risk has become more than just a hypothetical scenario, for which we need to prepare," said Paolo Gentiloni, EU commissioner for the economy.
"A storm is possible, but we are not there at the moment."
Germany, Europe's largest economy, is heavily reliant on Russian energy, with gas supplies from Russia accounting for 55% of Germany's gas imports in 2021.