Ukraine announced Thursday that it was forced to cede some territory in the east of the country under pressure from the Russian attack, while the Secretary-General of the North Atlantic Treaty Organization (NATO) stressed that Moscow should not be allowed to win the war.

Ukrainian President Volodymyr Zelensky described the pressure on his armed forces in the eastern Donbass region as "hell".

He spoke of fierce fighting around Avdiivka and the fortified village of Pesky, with Kyiv admitting that "the Russian enemy has achieved partial success" in the past few days.

On Thursday, the Ukrainian military said that Russian forces launched at least two attacks on Peske, but that its forces managed to repel them.

General Oleksiy Gromov told a news conference that Ukrainian forces had recaptured two villages around the eastern city of Sloviansk, but had retreated to the outskirts of Avdiivka after being forced to abandon a coal mine that is a key defensive position.

On the other hand, the Russian Defense Ministry confirmed its attack.

It said its forces inflicted heavy losses on Ukrainian forces around Avdiivka and two other outposts in Donetsk Province, forcing the withdrawal of mechanized infantry units in Kyiv.

Russia has said it plans to take full control of the wider Donetsk region, one of two that make up the industrial Donbass region, as part of what it calls a "special military operation" to protect its security from what it says is an unjustified expansion of NATO.

In a report on Thursday, Amnesty International accused Ukraine of endangering civilians by deploying troops in residential areas during the war, while Kyiv described the human rights organization's report as similar to Russian propaganda.

Ukraine and the West, which describe Russia's actions as an unjustified war of aggression, say Russian forces should withdraw to their positions before February 24, when President Vladimir Putin sent tens of thousands of troops into Ukraine.

For his part, Ukrainian President Volodymyr Zelensky said that Moscow is not offering his country dialogue but surrender.

He noted that the Kremlin had rejected all his attempts to talk to his Russian counterpart, Vladimir Putin, over the past three years.


NATO warning

In turn, NATO Secretary-General Jens Stoltenberg said on Thursday that the war was the most dangerous moment for Europe since World War II, and that Russia should not be allowed to win it.

He added that in order to prevent Moscow from achieving victory, the alliance and its member states may have to support Ukraine with weapons and other assistance for a long time to come.

"It is in our interest that this kind of aggressive policy does not work," Stoltenberg said in a speech in his native Norway.

Amid concerns among some politicians in the West that Russia's ambitions may extend beyond Ukraine, Stoltenberg warned Putin that the response to such a move by the Western military alliance would be overwhelming.

"If President (Vladimir) Putin thinks, just think, of doing something similar to a NATO member country as he did in Georgia, Moldova and Ukraine, the alliance will intervene immediately," he said.

sanctions

Meanwhile, the European Union imposed sanctions Thursday on ousted Ukrainian President Viktor Yanukovych, a pro-Russian, and his son, Oleksandr, for their alleged involvement in endangering Ukraine's security.

A European Council statement said the two men were included in the list of people subject to EU sanctions, which was drawn up "in response to Russia's unjustified military aggression against Ukraine".

Yanukovych assumed the presidency of Ukraine between February 2010 and February 2014, when he was overthrown in a popular uprising in protest of his government's turning its back on the West and its closeness to Russia.

Russian President Vladimir Putin responded to the defeat of his ally by seizing Crimea and an enclave in the Donbass region in eastern Ukraine.

The European Union considered that Yanukovych, 72, who lives in Russia, plays a "role in undermining or endangering Ukraine's territorial integrity, sovereignty, independence, stability and security."

The sanctions document published on Thursday in the Official Journal of the European Union accuses Yanukovych of plotting to return to power in Ukraine if Russia manages to oust President Volodymyr Zelensky.

Sanctions were also imposed on his son, Oleksandr, 49, for the same reason and for "conducting financial transfers to separatist groups in the Donbass region of Ukraine", in reference to pro-Russian forces.