Russian gas was still flowing to Europe today despite a deadline set by President Vladimir Putin to cut it off unless customers start paying in roubles.

This was Moscow's strongest threat to retaliate for sanctions imposed over its invasion of Ukraine.

Negotiations aimed at ending the war were set to resume by video link, with Ukrainian forces making more advances on the ground in a counterattack that has repelled the Russians from Kyiv and broken the sieges of some cities in the north and east.

After failing to capture a single major Ukrainian city in five weeks of war, Russia says it has shifted its focus to the southeast, where it has backed separatists since 2014.

The area includes the port of Mariupol, scene of the war's worst humanitarian emergency, where the United Nations believes thousands of people have died after more than a month under Russian siege and relentless bombardment.

Western sanctions imposed over the war have cut off Russia from much of world trade, but exceptions have been carved out for oil and gas.

Mr Putin signed an order setting a deadline today for buyers from "unfriendly" countries to pay for gas using roubles or be cut off, a demand Western customers have rejected as an attempt to rewrite contracts that call for payment in euros.

Germany, the biggest buyer, called it "blackmail", and had warned this week of a potential emergency if supplies were curtailed.

But there was no sign today of an immediate interruption.

Flows remained steady through two of the three main pipelines bringing Russian gas into Europe - Nord Stream 1 across the Baltic Sea, and into Slovakia over Ukraine.

Flows through the other main route, the Yamal-Europe pipeline over Belarus, had reversed direction, now bringing gas from Germany to Poland, but this occurs occasionally and did not necessarily indicate a new policy.

Gazprom, Russia's state-owned gas giant, said it was continuing to supply Europe via Ukraine in line with requests from consumers that were down only fractionally from yesterday.

A source had told Reuters that some contracts involved gas being delivered before payments were due, suggesting the taps might not be turned off immediately.

Govt plans to prevent fuel rationing - Vardakar

The Tánaiste has said the Government does not anticipate that energy rationing will be necessary next winter

Leo Varadkar said there is a concern about the supply of diesel over the next few months and possibly of gas if the Russians were to cut off supply, but he expects the contingency plans made by Government will prevent any need to ration.

He said it will be encouraging conservation.

Mr Varadkar said as Ireland does not rely on Russian gas it would not be affected directly if Mr Putin were to shut off supply, but it would on Ireland's European partners and that could have knock on effects for Ireland.

He said he thinks people understand the price of fuel and energy is driven by international factors and while the Government is doing a lot no government can fully protect against the prices rises driven by international markets.