Mr Sanders — a leading candidate for the Democratic presidential nomination — went after the president on Twitter just hours before Mr Trump was scheduled to touch down in California to view a renovated portion of border wall.
“We have a president who is a racist, a sexist, a bigot and a homophobe,” Mr Sanders said. “I wish I didn’t have to say that, but it is the damn truth. And we have to say it.”
The senator’s tweet comes just before he is set to speak at the National Action Network Convention in New York, an annual event hosted by Reverend Al Sharpton that is an important opportunity for candidates to court the support of black civil rights leaders.
Mr Sharpton’s non-profit group has been around for nearly three decades, and the conference is an opportunity for politicians to mingle with civil rights leaders and celebrities as they make their case for support during the election.
Snubbing the conference is viewed as a major faux pas among those influential members who congregate, and the event has been attended by Republicans and Democrats alike.
Among those who have attended in recent memory have been Donald Trump in 2002, as well as Bill Clinton in 2007 on behalf of his wife, Hillary Clinton. Barack Obama also attended the event while running for president.
But, while Republicans are known to attend, the event has broader significance in the Democratic party, which relies heavily on African American voters.
The demographic is expected to make up 12.5 per cent of the American electorate in 2020, and makes up a major portion of the Democratic base.
And, in early primary states like South Carolina — the first to vote in the South — African Americans make up nearly a third of the vote.
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