Ukraine marked 100 days since Russia's invasion on Friday with fighting raging across the east of the country, where Moscow's forces are tightening their grip on the Donbas.
The sombre milestone came as Kyiv announced Moscow was now in control of a fifth of Ukrainian territory, including Crimea and parts of the Donbas seized in 2014.
After being repelled from around the capital, President Vladimir Putin's troops have set their sights on capturing eastern Ukraine, prompting warnings the war could drag on.
Following White House talks with US President Joe Biden, NATO chief Jens Stoltenberg warned Thursday that Ukraine's allies needed to brace for a gruelling "war of attrition".
"We just have to be prepared for the long haul," Stoltenberg said, while reiterating that NATO does not want direct confrontation with Russia.
Despite a slower than expected advance, Moscow's forces are making progress -- President Volodymyr Zelensky told Luxembourg lawmakers about 20 percent of Ukrainian territory was now in Russian hands.
Since Russia's February 24 invasion, thousands of people have been killed and millions forced to flee. On the battlefield, up to 100 Ukrainian soldiers are dying every day, according to Zelensky.
Street battles are raging in the industrial hub of Severodonetsk in Lugansk, part of the Donbas.
Russia already controls about 80 percent of the strategic city but its defenders are putting up stiff resistance, with Lugansk regional governor Sergiy Gaiday vowing Ukrainian forces will fight "until the end".
Severodonetsk's Azot factory, one of Europe's biggest chemical plants, was targeted by Russian soldiers who fired on one of its administrative buildings and a warehouse where methanol was stored.
- 'Shooting is everywhere' -
Ukrainian troops were still holding an industrial zone, Gaiday said, a situation reminiscent of Mariupol, where a huge steel works was the southeastern port city's last holdout until Ukrainian troops finally surrendered in late May.
In the city of Sloviansk, about 80 kilometres (50 miles) from Severodonetsk, residents said there were constant bombardments by Russian troops.
"It's very difficult here," said paramedic Ekaterina Perednenko, 24, who only returned to the city five days ago but realises that she will have to leave again.
"Shooting is everywhere, it's scary. No water, electricity or gas," she said.
In the southern city of Mykolaiv, Russian shelling killed at least one person and injured several others, Ukrainian military officials said late Thursday.
Valeriy Zaluzhnyi, the commander in chief of Ukraine's armed forces, pleaded for modern armaments, saying that "the enemy has a decisive advantage in artillery."
"It will save the lives of our people," he added.
- Financial squeeze -
Led by the United States, Western nations have pumped arms and military supplies into Ukraine to help it survive the onslaught.
Bridget Brink, the new US ambassador to Kyiv, promised Thursday that the United States would "help Ukraine prevail against Russian aggression," after presenting her credentials to Zelensky.
Earlier this week, the United States announced that it was sending more advanced Himar multiple rocket launch systems to Ukraine.
The mobile units can simultaneously fire multiple precision-guided munitions at targets up to 80 kilometres away.
They are the centrepiece of a $700 million package that also includes air-surveillance radar, ammunition, helicopters and vehicles.
Kremlin spokesman Dmitry Peskov accused Washington of "adding fuel to the fire," although US officials insist Ukraine has promised not to use them to strike inside Russia.
Beyond sending arms to Ukraine, Western allies have also sought to choke off Russia's financial lifeline in a bid to get Putin to change course.
Ramping up an already long list of embargoes, the United States blacklisted Putin's money manager and a Monaco company that provides luxury yachts to Moscow's elite.
Across the Atlantic, EU nations agreed new sanctions that would halt 90 percent of Russian oil imports to the bloc by the end of the year.
- Oil move disappoints -
Russia warned that European consumers would be the first to pay the price for the partial oil embargo.
Major crude producers agreed to boost output by about 50 percent more a month in an effort to calm an overheated market and ease pressure on inflation.
But the move disappointed investors, and prices rose following the announcement.
The war risks triggering a global food crisis, as Ukraine is one of the world's top grain producers.
It was already translating into higher costs for essentials from cereals to sunflower oil to maize, with the poorest among the hardest hit.
The head of the African Union, Senegalese President Macky Sall, is to visit Russia on Friday for talks with Putin.
The visit is aimed at "freeing up stocks of cereals and fertilisers, the blockage of which particularly affects African countries", along with easing the Ukraine conflict, Sall's office said.
Latest developments
Here are the latest developments in the war in Ukraine:
- Street fighting in Severodonetsk -
Ukrainian forces pledge to fight "until the end" in Severodonetsk but with Russian forces in control of most of the key eastern city, their prospects of success appear slim.
"Street fighting continues," Lugansk regional governor Sergiy Gaiday says on Telegram, estimating 80 percent of the city is in Russian hands.
Lugansk is one of two regions, along with Donetsk, that make up Ukraine's industrial heartland Donbas which Russia has vowed to "liberate".
Once in control of Severodonetsk, Russian forces will likely try cross the Donets river flowing through it to target nearby Donetsk, according to a British defence ministry intelligence note.
- Russia controls 20 percent of Ukraine: Zelensky -
Ukraine President Volodymyr Zelensky says Russia controls about one-fifth of his country, from the ground gained since the February 24 invasion to the annexed Crimean peninsula and territory held by Moscow-backed separatists since 2014.
"Today, about 20 percent of our territory is under the control of the occupiers," the Ukrainian leader tells EU lawmakers.
Zelensky says in 2014, the separatists and the Russian military gained control of 43,000 square kilometres (16,600 square miles) of territory, but says that has increased to nearly 125,000 square kilometres -- an area "much greater" than the Netherlands, Belgium and Luxembourg combined.
- 'EU oil embargo to hit Europeans' -
Russia warns that European consumers will be the first to suffer after Brussels introduced a partial embargo on Russian oil over Ukraine.
"As a result of these decisions, European consumers will suffer above all," Russian Deputy Prime Minister Alexander Novak says, adding there may be a "big deficit" of oil products in the European Union.
On Monday, the EU agreed to a sixth package of sanctions on Moscow that will see the majority of Russian oil stopped, but exempted supplies by pipeline in a concession to Hungary.
- AU chief to meet with Putin on food -
African Union head, Senegalese President Macky Sall, will meet President Vladimir Putin in the Black Sea resort of Sochi on Friday to discuss food shortages caused by the conflict, which are exacerbating hunger in parts of Africa.
Both Ukraine and Russia are major suppliers of wheat and other cereals to Africa, while Russia, which is under export-limiting Western sanctions, is a key producer of fertiliser.
Sall's office says the visit, proposed by Putin, is aimed at "freeing up stocks of cereals and fertilisers."
- Danes vote to join EU defence policy -
Danes vote overwhelmingly in a referendum to join the EU's common defence policy 30 years after the NATO member opted out.
Almost 67 percent of people in the traditionally eurosceptic country back the move, which comes hot on the heels of neighbouring Finland's and Sweden's historic applications for NATO membership.
- Sweden ramps up aid -
Sweden announces additional aid of one billion kronor ($102 million, 95 million euros) to Ukraine, consisting of both financial aid and military equipment including anti-ship missiles and anti-tank launchers.
In late February, after the invasion began, Sweden broke its longstanding doctrine of not sending weapons to countries in active conflict.
Last month, Sweden, along with neighbouring Finland, in May overturned decades of military non-alignment by submitting historic joint applications to join NATO.
- Hundreds of "mercenaries" killed -
Moscow says it has managed to stem the arrival of foreign "mercenaries" in Ukraine over the past month and has killed "hundreds".
"Hundreds of foreign mercenaries in Ukraine have been destroyed by Russia's long-range precision weapons shortly after their arrival" to undergo training, the Russian defence ministry states.
- Putin money man blacklisted -
The United States places Russian President Vladimir Putin's money-manager and a Monaco provider of luxury yachts to Moscow's elite on its sanctions blacklist.
Washington hit Sergei Roldugin, labelled "Putin's middle-man," Roldugin's opera singer wife Elena Mirtova, and foreign ministry spokeswoman Maria Zakharova with sanctions, as well as several large yachts in which Putin allegedly has an interest, the US Treasury says.
- Russia ready to settle debt disputes -
Russia says it is ready to directly settle any disputes with its creditors after missing payments on its foreign debt due to Western sanctions over Ukraine.
Punishing Western sanctions on Russia have largely severed the country from the international financial system, making it difficult for Moscow to service its debt.