Vice President Kamala Harris called President-elect Donald Trump on Wednesday to congratulate him on his election victory, a senior Harris aide said.

The person spoke on condition of anonymity to discuss the call.

The aide said Harris discussed the importance of a peaceful transfer of power with Trump ahead of her planned concession speech Wednesday afternoon.

Harris will deliver a concession speech Wednesday at 4 p.m., her office announced.

Harris will speak at Howard University, her alma mater in Washington, where her supporters watched returns Tuesday night before being sent home after midnight as Trump pulled ahead in battleground state results.

Harris was scheduled to speak at Howard on Tuesday night and the atmosphere at the event was jubilant as initial results rolled in. As the night dragged on and it became clear that Harris would not defeat Trump, her supporters grew dour.

Cedric Richmond, Harris’ campaign co-chair, then told the audience they “won’t hear from the vice president tonight.”