The Belogorsk-Khabarovsk pipeline is designed to connect the China-bound Power of Siberia with the existing Sakhalin-Khabarovsk-Vladivostok link.
"Design and survey work is underway on other (connectors)," Gazprom said, without elaborating.
Russia has long sought to connect its vast western gas grid, which serves Europe, with its still-developing eastern pipeline network. An ability to redirect gas flows is seen as key to bolstering its negotiating position with buyers.
That has become more pressing due to the political fallout from the conflict in Ukraine, during which flows of Russian gas to Europe have dropped sharply. That has led to Russia looking to forge closer ties with Asia, especially with the world's No.2 energy consumer China.
Russia is seeking to boost pipeline gas exports to China through the construction of the Power of Siberia 2 pipeline, which is designed to carry 50 billion cubic metres (bcm) of natural gas a year from the Yamal region in northern Russia to China via Mongolia.
That is almost as much as the now idle Nord Stream 1 pipeline to Europe under the Baltic Sea that was damaged by blasts in 2022.
However Moscow and Beijing have not yet reached an agreement on key terms, especially on the price of gas.
Russia currently exports gas to China through the Power of Siberia 1 pipeline, which began operating in 2019. Annual gas exports via the pipeline are scheduled to reach 38 bcm by 2025.
