Former U.S. President Barack Obama plans to endorse Vice President Kamala Harris as the Democratic 2024 presidential candidate soon, NBC News reported on Thursday.

Obama privately has fully supported Harris' candidacy and has been in regular contact with her, the report, opens new tab said, citing people familiar with the discussions.

"Aides to Obama and Harris also have discussed arranging for the two of them to appear together on the campaign trail, though no date has been set," the report said.

With no one stepping up to challenge Harris for the nomination, she won the backing of party delegates on Monday, a day after President Joe Biden announced that he was dropping his reelection bid.

The Obama Foundation did not immediately respond to a Reuters request for comment.