Trump impeachment: What's Ukraine got to do with it?

The impeachment trial of US President Donald Trump is about to begin.

While all the wrangling between Democrats and Republicans over this case has been based exclusively in Washington, the reason Mr Trump has been impeached lies thousands of miles away on another continent.

Paul Adams, BBC diplomatic correspondent, has been to Ukraine to find out why it is so closely-linked to the Trump trial.

Hear more: The Inquiry: Why does Ukraine have such a corruption problem?