He said the volumes would exceed the contractual obligations of 22 bcm.
Natural gas supplies from Russia to China via Power of Siberia are due to reach the planned peak of 38 bcm in 2025, Miller said. The exports via the route started in the end of 2019.
Russia has also been in talks for years about building the Power of Siberia-2 pipeline to carry 50 billion cubic metres of natural gas a year from the Yamal region in northern Russia to China via Mongolia - almost matching the volumes the now idle Nord Stream 1 pipeline that was damaged by explosions last year used to carry under the Baltic Sea.
The plan has gained urgency as Moscow aims to double its gas exports to energy-hungry China to make up for the collapse of its exports to Europe following the start of the conflict in Ukraine in February 2022.
But agreement on key issues including pricing remains elusive.
In February 2022, Beijing also agreed to buy gas from Russia's Far East island of Sakhalin, which will be transported via a new pipeline across the Japan Sea to China's Heilongjiang province, reaching up to 10 bcm a year.
Miller said the supplies via that route will start no later than in 2027.