Decision on Russian oil embargo looms as civilian deaths mount

"We are working on a fifth round of sanctions and many new names are being proposed," said a senior EU diplomat, who spoke on condition of anonymity because of the sensitivity of the discussions.

The most forceful push, though, is coming from the countries that feel most threatened by the Russian war of aggression in Ukraine.

Lithuania's foreign minister Gabrielius Landsbergis said the EU cannot "get tired" of sanctions and he stressed that it was "unavoidable" to start discussing a ban on Russian oil imports.

"The credibility of the West is on the line," Landsbergis said, who emphasised the civilian suffering.

"We have to start [a] discussion about the 'red lines' [but] are there any? — and what would they be?" he told reporters on arrival on Monday. "We are seeing thousands of civilians dead, obviously it is still not a 'red line'."

The Lithuanian minister said the two other Baltic states, Latvia, Estonia, including his own country, are in "desperate need" of extra defence measures.

He urged EU countries to send Javelin and Stinger missiles to Ukraine "instead of hopes and prayers."

Nato, Biden, G7

The EU is expected continue the discussion on sanctions in the run-up to the meeting with Biden on Thursday for a series of summits involving the 27 EU heads of state and government, the 30 Nato members; and the Group of Seven (G7) format that includes Japan and the UK.

The EU, along with the Western allies, has already imposed a variety of far-reaching sanctions on Moscow including freezing the assets of the Russian Central Bank and cutting investments in the Russian energy sector.

But the bloc still faces its toughest economic choice — whether to target Russian energy directly, as the US and the UK have done.

That decision is comparatively difficult for the EU as several member states are dependent on Russian gas and oil, and energy prices have already soared in many European countries.

Baltic countries, such as Lithuania, are pushing for an oil embargo as the next logical step, while Germany, one of the most cautious countries, is warning against acting too quickly because of factors including the high energy prices.

The EU relies on Russia for 40 percent of its gas, and Bulgaria, for instance, is almost completely dependent on gas supplies from Russia's Gazprom.

Despite the dependencies, some countries' foreign ministers, like Ivan Korcok of Slovakia, insist that energy sanctions "must remain on the table."

By "receiving energy from Russia, we continue to fund Russia" and this "must be stopped," said Korcok. He pointed out that Slovakia itself depends 100-percent on Russian oil, and 85-percent on Russian gas.

Danish foreign minister Jeppe Kofod said his country supports "the strongest possible sanctions," including limiting Russia access to European sea ports.

European diplomats have previously indicated that a Russian chemical weapons attack in Ukraine, or a heavy bombardment of the capital Kyiv, could be a trigger for an energy embargo.

Ministers also expressed outrage over Moscow's targeting of civilians, and the unrelenting and terrifying assault on the city of Mariupol.

"Russia is committing a lot of war crimes," said EU foreign affairs chief Josep Borrell, arriving at the meeting Monday. And, he added, what "is happening in Mariupol is a massive war crime."