Jeanette Jalil

And until President Trump came to power, it was the U.S.

that was the biggest backer in Ukraine's war against Russia.

So it's striking, but perhaps not surprising, that no senior official from the Trump administration is there in Kiev today.

But there have also been complaints in Ukraine that the U.S.

is supplying more pressure on Kyiv than it is on Moscow.

Abduljaleel Abdulrasulov in Kiev.

Well, on this fourth anniversary, the Kremlin spokesman, Dmitry Peskov, admitted that the war in Ukraine had changed Russia and that President Putin had not reached all his goals in what he's still calling a special military operation.

Yes, it is true.

All the goals of the special military operation have not yet been achieved.

Western officials say that over the past three months, Russia has lost more troops than it's been able to recruit.

And over the past four years, it's estimated that well over a million Russian troops have been killed or wounded, staggering losses even for a country as big as Russia.

Few people there have dared to speak out publicly against the conflict after the initial protests were crushed.

But over the past year, four Russian soldiers have worked in secret with the BBC for a documentary called The Zero Line Inside Russia's War.

Here's an interview with one of them, a former Russian army medical officer called Dima.

Anna Foster asked him how he ended up serving in the Russian army.

When you joined the fighting, what about the other soldiers?

Did they feel the same way as you?

you didn't want to be involved in what's known as a meat storm.

It's a word that some people might not have heard before.

What did it mean to you?