It is too early to speak of the Ukraine crisis being solved despite tentative signs that diplomacy is making progress, German Chancellor Olaf Scholz said.
Mr Scholz’s remarks came as Berlin reported a dip in gas reserves that heavily depend on imports from Russia.
Diplomatic efforts went into overdrive this week as European governments scrambled to stop the Russian military build-up near Ukraine from exploding into war.
Britain took its turn spearheading those efforts on Wednesday with Foreign Secretary Liz Truss flying to Moscow to tell Russia that negotiations were the only way forward.
In Berlin, Mr Scholz said Russia had understood the oft-repeated message that it would face heavy sanctions if it invaded Ukraine.
Ukraine separately made upbeat noises on Wednesday, with Foreign Minister Dmytro Kuleba saying that “diplomacy is continuing to lower tensions”.
Mr Scholz said the discussions were a good sign but that the problems in East-West relations “are so serious and will remain for some time yet, so they deserve our attention”.
"It's much too early too say the problems have been solved," he said.
The political tension coincides with an energy squeeze in Europe that has sent prices soaring – leading to fears of Russia using its ample gas supplies as a bargaining chip.
A spokeswoman for Germany’s Economy Ministry said gas stocks, at about 35 per cent of storage capacity, were below the 40 per cent threshold deemed necessary to withstand a seven-day cold snap.
Those storage facilities should be half full to overcome a 30-day streak of cold weather.
“Of course we are monitoring the situation of the storage levels and that is certainly worrying,” the spokeswoman said.
Russia is Germany’s biggest gas supplier and the future of Nord Stream 2, an unopened gas pipeline between the two countries, is a bone of contention between Berlin and its Nato allies. Mr Scholz would not be drawn on the subject on a visit to Washington on Monday.
European Commission president Ursula von der Leyen told a German newspaper this week that there were "increasingly signs that the Kremlin is using gas deliveries as political leverage".
Russia, for its part, played down suggestions that a settlement was close after French President Emmanuel Macron claimed to have secured assurances from his counterpart, Vladimir Putin, in Moscow.
“In the current situation, Moscow and Paris can’t be reaching any deals,” said Kremlin spokesman Dmitry Peskov.
Mr Macron had said Russia would not escalate the situation in Ukraine, which is bracing for a potential invasion by the 100,000 troops assembled on its eastern flank. The US says an invasion could happen any day.
Russia also poured cold water on the visit from Britain's Foreign Secretary Liz Truss, who took a somewhat more strident tone ahead of her two-day trip to Moscow.
It said negotiations with the UK would be brief if Britain does not dial back its rhetoric on potential sanctions that could target wealthy Russians in London.
“If they're coming to Russia to threaten us again with sanctions then it is fairly pointless: we read everything, see everything, know and hear," said Russian ambassador in London Andrey Kelin.
Ms Truss had said that Russia “should be in no doubt about the strength of our response” if it invades Ukraine.
Britain’s role in negotiations will continue on Thursday when Prime Minister Boris Johnson visits Nato headquarters and then heads to Poland.
Mr Scholz, meanwhile, confirmed that top officials from Germany, France, Russia and Ukraine would meet in Berlin on Thursday in the hope of reviving peace efforts.
Russia and Ukraine each accuse the other of breaching the Minsk accords that were meant to bring peace to war-torn eastern Ukraine.
Mr Scholz is expected in Moscow next week.
