Vice President Joe Biden waves before speaking to students as part of the national It's On Us Week of Action at the Cox Pavilion at UNLV on April 7, 2016 in Las Vegas, Nevada.
Ethan Miller/Getty Images
Vice President Joe Biden waves before speaking to students as part of the national It's On Us Week of Action at the Cox Pavilion at UNLV on April 7, 2016 in Las Vegas, Nevada.
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Story highlights

Elizabeth Warren and Joe Biden "discussed" the idea of presidential ticket, according to a source familiar with the talks

Sources said the vice president never made a final decision about a running mate and he eventually decided not to run

(CNN) —  

Vice President Joe Biden “discussed” with Elizabeth Warren last year the idea of having her as his running mate for a would-be presidential bid, a source familiar with their conversations told CNN on Thursday.

But that source said nothing was offered and another said Biden never made a final decision.

A source close to Biden said the two met “several times” over the course of the last year and “walked around” the idea of a joint ticket and that Biden wanted to establish a rapport with the Massachusetts senator. He knew that if he were to run for president, “he needed to build his credibility on the left and she knew he would need her blessing,” the source said.

The resurgence of the idea for a Biden-Warren ticket comes a pivotal time for Democrats as the presidential primary draws near its end with its front-runner Hillary Clinton, who appears to have a nearly insurmountable delegate lead, heading to the finish line as her opponent, Bernie Sanders, continues to win states.

The source close to Biden also cautioned that the vice president had not yet decided whether he would actually run. Biden ultimately decided against it in October.

Biden’s office declined CNN’s request for comment on this story, as did Warren’s.

Politico first reported Thursday that Biden wanted Warren to be his running mate. The source familiar with Warren and the vice president pushed back on the notion that Biden had made a definitive decision to have Warren as his running mate.

CNN reported in August that Warren and Biden had met for two hours to discuss economic policy at the Naval Observatory. At the time, a person familiar with the discussion told CNN neither the presidential campaign or Biden’s future were a particular focus of the discussion.

RELATED: Biden meets with Warren in Washington

Warren was asked whether Biden had talked to her about a joint ticket by the Boston Globe in September. Warren simply responded, “It was a – a – long conversation.”

In recent days, the senior senator from the Bay State has staked out her own position in the 2016 presidential campaign as a vocal opponent to the presumptive Republican nominee Donald Trump, using his medium of choice – Twitter – to regularly rebut the real estate mogul in sharp 140-character attacks. Warren has not endorsed a candidate in the Democratic presidential primary.

Biden has repeatedly made news since he decided against a bid saying he regrets “every day” his choice not to run and has offered praise of both Sanders and Clinton. This week he told ABC News he expects Clinton to win the nomination and the general election.

RELATED: Elizabeth Warren gives Trump a dose of his own medicine on Twitter