Belarus on Tuesday ordered a shutdown of Russian gas transit deliveries to Europe, as Moscow insisted the latest energy feud with its ex-Soviet neighbour would not hit supplies to European clients.
Belarus' maverick leader President Alexander Lukashenko ordered the move after Moscow slashed supplies to Minsk in a row over unpaid debts, the fiercest in a string of two-way disputes over energy prices and trade.
In a televised remarks during a meeting with Russian Foreign Minister Sergei Lavrov, Lukashenko warned the conflict was turning into a full-blown "gas war" and that he would not tolerate humiliation by Moscow.
Moscow accuses Minsk of failing to settle a debt of 192 million dollars (156 million euros) to Russian gas giant Gazprom, but Belarus says the firm also owes it more than 200 million dollars in transit fees.
The Belarussian president said Tuesday Minsk had found the money to pay his country's debt to Gazprom by borrowing from "friends" and that it would settle its debt "shortly".
But he also insisted Russia owed money to Belarus.
"I have now ordered the government to shut down transit through Belarus until Gazprom pays for transit," Lukashenko said.
Lukashenko slammed Russian President Dmitry Medvedev, who said Monday after Belarus offered to foot the bill with machinery and equipment that Russia could accept "neither pies nor butter nor cheese nor pancakes".
"The Russian leadership's statement humiliates the Belarussian people," Lukashenko told Lavrov. "I am sorry, when they start humiliating us with either cutlets or sausages or butter or pancakes, we perceive this as an offence to the Belarussian people."
Russia cut its normal daily gas supplies to Belarus by an initial 15 percent on Monday after Minsk failed to act to settle its debt.
On Tuesday it announced it was reducing supplies by 30 percent and warned the cuts could reach 85 percent if the debt is not settled in the coming days.
The energy row has raised the spectre of a 2009 dispute between Russia and Ukraine, when supplies to European customers were cut off for two weeks in the dead of winter.
Europe has activated crisis planning measures faced with the dispute and the EU Commission on Tuesday called on Belarus and Moscow to respect their "contractual obligations".
European parliament president Jerzy Buzek, speaking during a visit to Moscow, said that pressure levels were lower than normal in gas pipelines in Lithuania, Germany and eastern Poland.
"The volumes being delivered are lower than expected," he was quoted as saying by Russian news agencies.
Later Belarussian first vice premier Vladimir Semashko said in televised remarks that Minsk had given the order to start diverting Russian gas bound for European markets "in order to support Belarus' gas supply system".
Gazprom spokesman Sergei Kupriyanov told AFP it was "possible" that further cuts would be decided on Wednesday, but pledged that Europe would not see any disruptions in gas supplies.
"There are no problems. We are convinced that our European customers will receive all necessary gas supplies in accordance with our contracts regardless of Minsk's actions," Kupriyanov said.
"Gazprom has begun exploring the possibilities of alternative gas supply for our customers in Europe," he said.
Back-up plans to keep gas flowing to Europe include an alternative route through Ukraine, through which most of Russia's gas to Europe already transits, as well as gas stored in Europe and a spot market.
Buzek said the European Union was prepared to send observers to monitor the transit of Russian gas -- as it has done in the past -- but would not get involved in the conflict.
Analysts said the impact of any potential disruptions would be less serious because of lower gas demand in the summer.
According to analysts, the dispute was triggered by Lukashenko turning away from Moscow and towards the European Union.
In Belarus, a senior official with the presidential administration accused Russia of seeking political revenge.
"They are trying to humiliate Belarus and settle accounts with it for its political position," the official told AFP on condition of anonymity.