Former US President Barack Obama and his wife Michelle will deliver speeches on the second day of the Democratic National Convention. The party is trying to unite in support of Vice President Kamala Harris ahead of the US presidential election in November.

The four-day event opened at a convention center in Chicago, Illinois on Monday. The former first couple will take the stage on Tuesday.

The Obamas are still popular with Democratic Party supporters. They are particularly popular among young voters.

The former president is expected to mention that he first met Harris 20 years ago, when she was a district attorney.

Senate Majority Leader Chuck Schumer and other party leaders are also scheduled to give speeches on Tuesday.

On Monday, the party adopted its policy platform, and President Joe Biden urged Democrats to unite behind Harris to defeat the Republican Party's candidate, former President Donald Trump.

Biden said, "Democracy has prevailed, democracy has delivered, and now democracy must be preserved."