A key ally of Donald Trump has revised his testimony in the impeachment inquiry and now says the US president offered a quid pro quo with Ukraine to investigate a political rival.

US ambassador to the European Union Gordon Sondland now acknowledges that American military aid to Ukraine was contingent on Kyiv investigating Joe Biden and his son for corruption.

This further strengthens the case against Trump.

Al Jazeera's Heidi Zhou-Castro reports from Washington, DC.

Code: MARCH. Get An Additional 20% Off on Clearance at Eastern Mountain Sports! Shop Now and Save!

More videos

CGTN 15 Dec 2019 08:30 CET

1 injured in U S mall shooting