The US president vows to be "the best volunteer" for Kamala Harris's election campaign. Addressing the party's National Convention in Chicago, an emotional Joe Biden told Democratic supporters that they are in a battle for the "very soul of America." The four-day event will confirm Harris as the Democratic presidential candidate to take on Donald Trump.

On this episode, Sumi Somaskanda is in Chicago with Courtney Subramanian and Bernd Debusmann from the BBC's digital team. They discuss what President Biden might do during his remaining time in the White House and the role he could play in the Harris-Walz campaign.

The Global Story brings you trusted insights from BBC journalists worldwide. We want your ideas, stories and experiences to help us understand and tell #TheGlobalStory. Email us at [email protected] You can also message us or leave a voice note via WhatsApp on +44 330 123 9480.

Producers: Peter Goffin and Richard Moran.

Sound Engineer: Matt Dean.

Assistant Editor: Sergi Forcada Freixas.

Senior Editor: Richard Fenton-Smith.