Pete Buttigieg discussed his withdrawal from the 2020 presidential race with former President Barack Obama who advised the one-time mayor of South Bend, Ind., to use the leverage he amassed during the campaign, according to a report.

Obama didn’t specifically encourage Buttigieg to endorse Joe Biden, his vice president, but pointed out that he should be mindful of the significant influence he now wields, the New York Times reported on Monday.

Buttigieg, 38, endorsed Biden on Monday on the eve of the Super Tuesday elections, along with erstwhile Democratic presidential rivals Sen. Amy Klobuchar of Minnesota and former Rep. Beto O’Rourke of Texas.

“When I ran for president we made it clear that the whole idea was about rallying the country together to defeat Donald Trump and to win the era for the values that we share,” Buttigieg said about Biden. “And that was always a goal that was much bigger than me becoming president and it is in the name of that very same goal that I am delighted to endorse and support Joe Biden for President.”

Buttigieg, the first openly gay man to run for president, also spoke to Biden after he dropped out and the candidate sought his support.

He told Biden that he wanted to sleep on the decision.

Obama also called Biden to congratulate him on his decisive win in South Carolina on Saturday, but didn’t offer an endorsement because the former president wants to remain on the sidelines, CNN reported.

He has no plans to back Biden or any of the Democratic candidates as yet.