Since Vice President Kamala Harris announced her presidential candidacy on Sunday, she and former President Barack Obama have been in frequent contact, engaging in multiple discussions this week, NBC News reported on Thursday citing sources.

Obama has privately expressed his complete support for Harris' campaign and is planning to endorse her in the near future, the sources added without mentioning a date.

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"He has been in regular contact with her and thinks she's been off to a great start," one said.

Obama is one of the few prominent Democrats yet to endorse Harris.

One source mentioned that the former president delayed his endorsement to avoid overshadowing Biden’s Wednesday address. Another source noted that Obama and Harris wanted the endorsement to be a distinct event.

Discussions are ongoing about Obama and Harris appearing together on the campaign trail. Additionally, Obama's wife Michelle supports Harris' candidacy, according to two sources.

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"President Obama looks forward to helping Democrats up and down the ballot make the case to voters this fall," said Eric Schultz, a senior advisor to Obama. "Our strategy will be based on driving impact, especially where and when his voice can move the needle."

In recent days, Obama has provided the vice president with advice on establishing her campaign and other strategies for a successful presidential bid.

Recognizing the significant challenges Harris has faced quickly, Obama sees himself as a resource for her. With about 100 days until Election Day, he aims to help unify the Democratic Party and support their forward movement. He is expected to be active in the campaign this fall.

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The only publicly known call between them occurred on Sunday, the same day President Joe Biden announced he would not seek re-election and endorsed Harris instead.

"We will be navigating uncharted waters in the days ahead," Obama said in the statement. "But I have extraordinary confidence that the leaders of our party will be able to create a process from which an outstanding nominee emerges."

Harris quickly gained endorsements nationwide, facing no challengers for the nomination.

Obama's private concerns about Biden's ability to defeat Trump in November, noted by NBC News earlier, did not translate into urging Biden to stay in the race, though Obama defended Biden's debate performance on social media.

Obama and Harris have a long-standing relationship, with Harris supporting Obama’s 2008 campaign, speaking at his 2012 nominating convention, and receiving his support in her bids for California attorney general and the Senate.

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