In an interview with Radio Sputnik, analyst Alexander Razuvaev said that this decision was triggered by political factors.
"From my point of view, the quality of Russian gas is well-known, it's standard. So I think there are political reasons for this decision: some Eastern European countries accuse Russia of baseless and even unrealistic things, they are ready to say anything. In general, I think that this is a nervous reaction amid the Nord Stream-2 construction," Razuvaev noted.
On Wednesday, Polish gas operator Gaz-System stopped gas deliveries through a reverse flow on the Yamal-Europe pipeline, citing "poor quality" of the gas.
"The Gaz-System gas trunk line operator reports that due to poor quality of gas it cannot receive fuel for the national gas transportation system… on the Yamal gas pipeline," the statement said.
In May, Poland's state-controlled oil and gas company PGNiG called on the European Commission to impose a fine on Gazprom for alleged violations of anti-monopoly legislation "for many years."
PGNiG head Piotr Wozniak was quoted by media reports as saying that "the European Commission should financially punish Gazprom and create competitive conditions in the gas market."
The Nord Stream 2 project presupposes the construction of two gas pipelines totaling a combined annual gas capacity of 55 billion cubic meters. The new pipeline is planned to be laid along the original Nord Stream pipeline route, starting from the Russian coast, then through the Baltic Sea to a hub in Germany.