VIDEO - Obama has taken active interest in Biden's campaign: report | TheHill

Former President Obama has taken an active interest in Joe Biden Joe BidenWarren leads Democratic field by 5 points in Wisconsin: poll O'Rourke says Trump 'terrorizing' immigrants in campaign relaunch speech Harris wins endorsement of former CBC Chair Marcia Fudge MORE 's presidential campaign, even holding a lunch with his former vice president last month, according to a report in The New York Times.

Obama also summoned top members of Biden's campaign to his Washington, D.C., home earlier this year for a briefing on Biden's communications and digital media strategies ahead of the former vice president's campaign launch.

Obama is not endorsing a candidate in the Democratic presidential primary, where polls show Biden is the front-runner.

He has pledged to stay neutral in the race and has made few forays into political life. An exception came last month when Obama warned against political leaders who give support to white supremacy and white nationalists, remarks that came after a deadly shooting in El Paso, Texas. The suspect in that shooting allegedly targeted Hispanics.

But the Times report states that Obama is watching Biden's campaign closely and has offered advice at different times.

The former president has reportedly urged Biden's campaign to include younger advisers, and the Times reported that Obama is frustrated with some of Biden's closest advisers, who he perceives as out of touch with the younger activist base of the Democratic Party.

Obama asked two Biden aides — spokeswoman Kate Bedingfield and former White House communications adviser Anita Dunn — to visit with him in March for a briefing on its strategy. Afterwards, the Times reported that Obama told the aides they should make sure that Biden does not “embarrass himself” or “damage his legacy” while running for president.

Biden has tied himself closely to Obama in his campaign, and his popularity, particularly with African American voters, has been largely attributed to his years in the Obama White House. 

In a Fox News poll published Thursday, Biden held first place overall with 31 percent of the vote compared to his closest competitor, Sen. Elizabeth Warren Elizabeth Ann WarrenWarren leads Democratic field by 5 points in Wisconsin: poll The danger of using race and politics to declare guilt or innocence Harris wins endorsement of former CBC Chair Marcia Fudge MORE (D-Mass.), who has moved into second place at 20 percent.