oscow's blockade of Ukrainian grain exports and a rail transit row sparked fresh tensions between Russia and the European Union on Monday, as Kyiv warned that Russian troops were intensifying their battle for control of eastern Ukraine.
Ukrainian President Volodymyr Zelensky accused Russia of holding Africa "hostage" by blocking wheat deliveries, which has spurred food shortages and fears of famines in vulnerable areas.
Nearly four months after Russia launched its bloody invasion, Zelensky said Ukraine was headed into a "fateful" week with EU leaders set to discuss Kyiv's bid to become a candidate for bloc membership on Thursday and Friday.
European Council President Charles Michel on Monday invited the bloc's leaders to back granting candidate status to Ukraine and Moldova ahead of the pivotal Brussels summit.
Zelensky warned to expect heavier fighting in the days to come in strategic areas in eastern Ukraine already under relentless Russian bombardment.
Ukraine said Russian troops appeared to be making small gains, including capturing a village near the industrial city of Severodonetsk, a focus of recent fighting.
The fallout from the war continued to reverberate beyond Ukraine's borders, with Russia threatening EU member Lithuania over its "openly hostile" restrictions on the rail transit of goods to Moscow's exclave of Kaliningrad.
Lithuania and EU foreign policy chief Josep Borrell said the ban was in line with European sanctions over Moscow's aggression.
Turkey dealt a fresh blow to Sweden and Finland's hopes for swift NATO membership on Monday, saying next week's alliance summit in Madrid was not a deadline.
NATO chief Jens Stoltenberg said talks between Turkey, Sweden and Finland in Brussels were "constructive" but conceded that Ankara's "legitimate" concerns had not been fully addressed.
Turkey says the Nordic nations offer a safe haven to the Kurdistan Workers' Party, an organisation listed as a "terrorist" group by its Western allies.
Elsewhere on the diplomatic front, US President Joe Biden said it was "not likely" that a trip to Europe this week would include Ukraine, after the leaders of France, Germany, Italy and Britain met Zelensky in Kyiv last week.
Biden is one of few Western leaders yet to visit the country since Russia's invasion.
- 'Complex' grain talks -
The West's deteriorating relationship with Moscow was highlighted in harsh comments from Borrell, who called Russia's blockade of vitally needed grain exports from Ukraine "a real war crime".
"One cannot imagine that millions of tonnes of wheat remain blocked in Ukraine while in the rest of the world people are suffering hunger," Borrell said as EU foreign ministers met in Luxembourg.
Moscow denies responsibility for the disruption to deliveries.
Russian foreign ministry spokeswoman Maria Zakharova on Monday called the West "provokers and destroyers", blaming its policies and anti-Russian sanctions for the logistical upheaval that has pushed up cereal prices and fanned fears of famines in vulnerable regions.
Zelensky said Ukraine was engaged in "complex multilevel negotiations" to end Russia's blockade of Ukrainian ports.
"But there is no progress yet... That is why the global food crisis will continue as long as this colonial war continues," he said in a video address to the African Union.
Germany said it will host a meeting on Friday on the crisis, with US Secretary of State Antony Blinken among those attending.
- Oil site strike -
On the ground, Ukraine's presidency said the intensity of shelling in the Donetsk area of the eastern Donbas region was "growing along the entire frontline", leaving at least one person dead over the last 24 hours and injuring seven others, including a child.
Ukraine announced it had lost control of the village of Metyolkine, adjacent to Severodonetsk.
In Severodonetsk, "Russians control most of the residential areas", the head of the city administration Oleksandr Stryuk told Ukrainian television Monday.
A chemical plant in Severodonetsk where hundreds of civilians are said to be sheltering was being shelled "constantly", Ukraine said.
Kyiv also reported heavier Russian shelling in the Kharkiv region in the northeast.
Crimea leader Sergey Aksyonov said three people were injured and seven more missing after Ukrainian forces attacked oil drilling platforms in the Black Sea off the coast of the peninsula annexed by Russia in 2014.
Aksyonov vowed that search and rescue operations would continue.
It was the first reported strike against offshore energy infrastructure in Crimea since Russia launched its invasion.
- Energy crisis -
The Ukraine war is fuelling not only a global food crisis but an energy crisis too.
Hit by punishing sanctions, Moscow has turned up the pressure on European economies by sharply reducing gas supplies, which has in turn sent energy prices soaring.
The Netherlands on Monday lifted restrictions preventing its coal-fired power stations from operating at full capacity to counter the fall in Russian gas supplies, a day after Germany and Austria took similar steps.
But Berlin insisted it still aims to close its coal power plants by 2030.
China's imports of oil from Russia meanwhile jumped by 55 percent year on year in May, customs data showed Monday, helping to make up for losses from Western sanctions as Beijing refuses to publicly condemn Moscow's war.