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The leaders of Poland, the Czech Republic and Slovenia were on their way to Ukraine’s capital on Tuesday on a mission to show support as Russia’s forces move deeper into Kyiv.
The visit by Slovenia's Janez Jansa, Poland's Mateusz Morawiecki and Czech leader Petr Fiala is the first by such a delegation since war broke out in Ukraine and was planned with the leaders of the European Union.
Their train trip to a city under bombardment was described by the Polish leader's chief of staff as "a historic event" and an "unequivocal expression of support for Ukraine" by the three EU member states.
The US said it welcomed the in-person trip but Julianne Smith, the American ambassador to Nato, would not be drawn on whether it threw up safety concerns for the three leaders.
No details about the itinerary were disclosed except that the three leaders were on their way via Lviv in western Ukraine and would meet with President Volodymyr Zelenskyy and Prime Minister Denys Shmyhal.
Mr Jansa used the opportunity to argue Ukraine's case for membership of the EU, an idea supported by many of its eastern neighbours but which senior western officials have said will not be fast-tracked.
"At this moment... there is no country on the whole of the continent which is more European than Ukraine," he said. "Every path in Ukraine is a European path. Soon, it will be an EU path too."
Russia’s offensive in Ukraine edged closer to central Kyiv on Tuesday, with a series of strikes hitting a residential neighbourhood in the capital as the two countries planned a second day of talks.
Shortly before dawn, large explosions thundered across Kyiv from what Ukrainian authorities said was artillery strikes.
The shelling ignited a huge fire and a frantic rescue effort in a 15-storey apartment building. At least one person was killed and others remain trapped inside.
After a relative lull, fighting has intensified on the outskirts of Kyiv in recent days, and sporadic air raid sirens ring out around the capital.
There was a rare glimmer of hope in the encircled port city of Mariupol after a convoy of 160 civilian cars left along a designated humanitarian route, the city council reported.
Over the past 10 days or so, the lethal siege has pulverised homes and other buildings and left people desperate for food, water, heat and medicine.
Meanwhile, Mr Zelenskyy will deliver a virtual address to US Congress on Wednesday.
“We look forward to the privilege of welcoming President Zelenskyy'sAaddress to the House and Senate and to convey our support to the people of Ukraine as they bravely defend democracy,” Speaker of the House of Representatives Nancy Pelosi and Senate majority leader Chuck Schumer said in a joint letter to politicians.
Anthony Rota, the Speaker of the Canadian House of Commons, said Mr Zelenskyy would also address MPs in Ottawa on Tuesday.
The fourth round of talks involving higher-level officials from Ukraine and Russia ended without a breakthrough after several hours on Monday, with an aide to Mr Zelenskyy saying the negotiators took “a technical pause” and planned to meet again Tuesday.
The two sides had expressed some optimism in the past few days.
Mykhailo Podolyak, an aide to Mr Zelenskyy, tweeted that the negotiators would discuss “peace, ceasefire, immediate withdrawal of troops and security guarantees”.
Mr Zelenskyy is seeking to extend martial law until April 24 and to require men aged 18 to 60 to stay in the country to fight.
He submitted the extension in a bill to parliament, which is expected to vote on it this week.
In Washington, White House press secretary Jen Psaki said that while the Biden administration supports Ukraine’s participation in the talks with Russia, Russian President Vladimir Putin would have to show signs of de-escalating to demonstrate good faith.