Vitaly and Victoria speak to Oleksandr Sosnovskyi, from the south-eastern city of Zaporizhzhia, as the city prepares in case of a Russian offensive.

We also catch up with Vitalii Pashchenko, a 19-year-old student, who says some lecturers have remained to teach as bombs go off around them.

There’s also a roundup of the latest developments after the highest-level trip to Ukraine by US officials since the invasion began.

Today's Ukrainecast was made by Estelle Doyle with Osman Iqbal and Chris Flynn. The technical producer was Gareth Jones. The editor was Jonathan Aspinwall.

The UN Human Rights Office has today described the war in Ukraine as a ‘horror story of violations against civilians’, in which respect for international law has been ‘tossed aside’. Matilda Bogner, who runs the UN's Human Rights Monitoring Mission in Ukraine, tells us about the war crimes they've documented.

We're also joined by the Marianna Spring, the BBC's disinformation reporter, who tells us the real story of the Ukrainian soldier who became famous when a clip of him defying orders from a Russian warship to surrender, and swearing at them, went viral.

And a daughter tells us how she undertook an extraordinary journey into the besieged city of Mariupol to rescue her parents.

Today's Ukrainecast was made by Estelle Doyle with Osman Iqbal and Alix Pickles. The technical producer was Cassie Galpin. The Editor was Jonathan Aspinwall.

The Russian President orders troops to seal off the port city.

Victoria speaks to defence expert, Justin Crump, about the situation in the city of Mariupol.

She also talks to a woman who had an emergency C-section in the basement of a hospital as the fighting was intensifying outside.

Anastasia Platonova from the BBC Russian Service – currently based in the Latvian capital, Riga – has been speaking to the mothers of Russian sailors who’ve gone missing.

And the BBC's Lewis Goodall returns to Poland to see how Ukrainian refugees are faring since his last visit.

Today's Ukrainecast was made by Estelle Doyle with Osman Iqbal and Ben Cooper. The technical producer was Emma Crowe. The assistant editor was Sam Bonham.

A Ukrainian marine commander in Mariupol has made what he described as his troops' "last address to the world" as they try to resist Russian forces in the city.

Victoria Derbyshire, James Landale, and Olga Malchevska speak to Olena Nikulina, whose cousin Maks is among the soldiers still there.

Also on the podcast, The Economist correspondent Oliver Carroll, who’s been speaking to a commander in the city.

And the BBC’s religion editor Aleem Maqbool discusses the Russian Orthodox Church's role in the conflict.

Today's Ukrainecast was made by Estelle Doyle with Osman Iqbal and Chris Flynn. The technical producer was Emma Crowe. The editor was Jonathan Aspinwall.

We speak to a Russian politician...

Yevgeny Popov, Deputy of the State Duma of the Federal Assembly of the Russian Federation, speaks to Frank Gardner and Victoria Derbyshire, and says that Russia felt “bullied” into invading Ukraine. He’s challenged on his belief that Nato is the aggressor, and his claims are analysed with the help of Sam de Bendern, a former Nato Ukraine political officer.

Today's Ukrainecast was made by Alix Pickles and Chris Flynn. The technical producer was Emma Crowe. The assistant editor was Sam Bonham.

Travelling 2000 miles from Poland to the UK...

When Ukrainecast listener, Richard O’Doherty, emailed us offering to drive Vitaly's mum and aunt from Poland to the UK, we did not know what to expect. But on the Easter weekend, Alla and Irena arrived into Reading, greeted by Vitaly and members of his family. And, having followed their story since the invasion began, Victoria joined them at Vitaly's house the morning after, to talk through this momentous journey and what it means for everyone involved.

This special episode of Ukrainecast was made by Emma Crowe. The technical producer was Mike Regaard. The assistant editor was Sam Bonham.

The Ukrainian president accuses Europe of paying for Russian oil with blood money. The Ukrainians claim to have hit Russia's flagship warship. And Finland eyes up a place in Nato.

On today's Ukrainecast Vitaly and Fergal also hear how Ukrainian Railways are playing a critical role in the war effort, after having to reinvent themselves to evacuate refugees and move supplies around the country.

And we have an eyewitness account from a young woman who fled from the Donbas region last week.

Today's episode was made by Phil Marzouk and Osman Iqbal. The technical director was Emma Crowe. The assistant editors were Alison Gee and Sam Bonham.

Ukraine says it has arrested one of President Putin’s allies and is interested in a prisoner swap. Viktor Medvedchuk had been under house arrest in Kyiv but escaped when the Russian invasion began. James Landale joins Victoria to discuss whether a swap is likely.

There's also an update from Hussain who fled from Kherson. He’s been helping other people escape from the same city - we speak to one of them.

Today's episode was made by Phil Marzouk and Chris Flynn. The technical director was Emma Crowe. The assistant editors were Alison Gee and Sam Bonham.

Reflections on the horrors inflicted on the people of his city...

After weeks of reports of Russian atrocities in the region surrounding Kyiv, the mayor of Bucha speaks to us and asks: “Why did they do this to us?”

You may remember Sasha Makoviy, the mother who wrote pertinent information and contact details on the back of her two-year-old daughter in case the worst happened. We hear the latest.

And we also speak to director of the Maidan museum in Kyiv who is striving to ensure the country’s artefacts are kept safe.

Today's episode was made by Chris Flynn and Phil Marzouk. The technical director was Emma Crowe. The assistant editors were Sam Bonham and Alison Gee.

The man involved in Syria and Chechnya is now reported to be in charge of operations in Ukraine. Victoria, Vitaly and Frank are joined by Reuters' former Moscow correspondent, Oliver Bullough, to discuss General Aleksander Dvornikov’s past and what this means for the war.

They also speak to Oleksandra Matviichuk, a human rights worker in Kyiv who’s just found out that her dad is alive after more than a month of no contact.

And, two very different diplomatic visits are on the agenda - Boris Johnson’s trip to Kyiv and the Austrian Chancellor’s visit to Moscow, making him the first Western leader to go there since the war started.

Today's episode was made by Alison Gee with Osman Iqbal and Chris Flynn. The technical director was Emma Crowe. The assistant editor was Sam Bonham.