Watch: Barack Obama backs Kamala Harris at Democratic National Convention

Obama criticises Trump's leadership as chaotic and praises Joe Biden for his commitment to democracy

Barack Obama endorsed Kamala Harris for US president, urging Americans to support her in the race against Donald Trump.

He criticised Trump's leadership as chaotic and praised Joe Biden for his commitment to democracy.

With Biden stepping down from the race, he threw his support behind Harris, who aims to become the first woman, and first Black and South Asian US president. 

The convention emphasised the importance of unity and the need for a new direction in American leadership.