Asked if there are guarantees that Gazprom will restart gas flows via Nord Stream 1, the Kremlin's Peskov said: "There are guarantees that, apart from technological problems caused by sanctions, nothing hinders the supplies."

A three-day halt of the Nord Stream pipeline -- a key source of natural gas for the European Union -- starts on Wednesday, and concerns are widespread that Moscow will find another excuse to clamp down on supplies, putting the region at the mercy of the weather.

Tokyo Gas and Japan's largest power generation company JERA said previously that they have signed new LNG supply agreements on the same terms as previous agreements. Sources said that new contracts were required due to the change of operator.

European natural gas prices on Monday plunged the most since March after Germany said its gas stores are filling up faster than planned.

Europe’s benchmark electricity price has risen to 10 times its decade-long average, in line with a 14-fold increase in the cost of gas, amid fears of shortages this winter.

With Russia squeezing gas deliveries and power-plant outages further sapping supply, pressure is growing on EU leaders to act quickly or risk social unrest and political upheaval.

Bern has been working to build up Switzerland's energy production and storage systems, but even the grand opening next month of a new, powerful pumped-storage hydroelectric plant is unlikely to help avoid problems this winter.

Japan's biggest city gas supplier Tokyo Gas Co Ltd has signed a long-term contract with a new Russian operator of Sakhalin-2 energy project to buy liquefied natural gas (LNG), a spokesperson for the Japanese company said on Tuesday.

Benchmark Dutch front-month futures fell as much as 16%, partly reversing last week’s jump of almost 40%.

"Today, the Paks II NPP project is taking another leap forward," said Hungary's Minister of Foreign Affairs and Trade Péter Szijjártó. "The construction licence confirms that the project complies with the international and Hungarian safety requirements. It is entirely feasible that Hungary will have two new power units by 2030, thus ensuring the stability of energy supply."

Alexander Korchagin, Atomstroyexport senior vice president for NPP construction project management, said the El Dabaa project - where construction formally began last month - is an attractive project for international companies. KHNP is joining a pool of qualified participants in the construction works, including major Egyptian companies, he added.

The station, as stated in the technical specification, must operate at temperatures from minus 60 to plus 40 degrees Celsius. The Automated Control and Management System (ACS) must ensure stable operation of the reactor or its shutdown without the participation of operational personnel.

While some countries like Germany, where nearly half the homes rely on gas for heating, are more exposed than others, the European Union is seeking to band together.

The EU’s sixth round of sanctions over the invasion of Ukraine includes a ban on Russian oil, as well as the use by third countries of the bloc’s companies for insurance and financial services.

Households in the Nordic country have already been told to prepare for rolling power cuts in the winter, as there will be no supplies from Russia to help meet peak demand.