Bernie Sanders Tells Hillary Clinton To Stop "Arguing About 2016" On The Stephen Colbert Show — VIDEO

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It's not news that the bad blood between certain fans of Sen. Bernie Sanders and some Hillary Clinton supporters is still brewing. But it seems that tension lingers between the two former Democratic candidates, too. After being confronted with some excerpts from Clinton's forthcoming memoir that don't cast him in the most flattering light, Sanders had a few words to say. Speaking as a guest on The Late Show with Stephen Colbert, Sanders said he wanted Clinton to move on from the election, saying, "Let's not keep arguing about 2016." Instead, he wants her to join the fight to advance the progressive agenda.

During the interview, Sanders also listed off some of his policy goals that he'd prefer Clinton to focus on, in lieu of rehashing the 2016 campaign:

I would like her to join us in the fight for a Medicare-for-all single payer system, in taking on the fossil fuel industry so that we transform our energy system away from fossil fuel and move to energy efficiency and sustainable energy... Let’s get together, take on Trump’s desire to divide us up. Let’s go forward with a progressive agenda. Ask her if she will do that.

It's a move many see as a subtle dig at Clinton's book — which has already garnered criticism among some circles — and perhaps Clinton herself. It's perhaps unsurprising that the senator from Vermont, known for his brusque manner of speaking, would be so forthright in his opinions about the best next steps for Clinton. The two candidates had faced off in a contentious primary, and the animosity clearly remains.

After her election defeat, Clinton laid low for a few months, only emerging to tweet occasionally, like when President Trump signed his travel ban executive order and she voiced her support for the massive protests against it. But she has slowly and surely returned to the public eye, and with her new book, What Happened, Clinton seems to be figuring out what her next move is — all under intense scrutiny, particularly from conservatives and leftists, many of whom, like Sanders, lament the book's focus on the election.

Sanders and his supporters are not alone in their opinion. At Politico, Edward-Isaac Dovere and Gabriel Debenedetti report that former Clinton campaign staff reacted to news of Clinton's new memoir with comments like, "Oh, God," "I can’t handle it," and "the final torture." Many seem eager to join in Sanders’ call to move on and focus on what can be accomplished in the future. And as Dovere and Debenedetti point out, Clinton’s approval rating is currently the lowest it has ever been, sitting at a dismal 30 percent.

Sanders holds a lot of sway in the party now. The enthusiastic response to the septuagenarian — especially from younger voters — took everyone by surprise in 2016, not least of all the party elders. Clinton was supposed to easily sweep through the Democratic primary. Instead, Democrats discovered there existed an appetite for more radical, less polished political presentation and policies. And whether they like it or not, many in the party have accepted the fact that Sanders holds a lot of cards.

Of course, Clinton has her own message about Sanders: He’s not the answer. Her memoir What Happened apparently puts heavy blame on Sanders’ shoulders for what went down in her subsequent contest with candidate Trump. The feud between Sanders and Clinton — and their stubbornly loyal supporters — is making it ever more difficult for Democrats to unite behind common goals.

Clinton will have a chance at a rebuttal to Sanders' comments from Thursday. She herself will sit down with Stephen Colbert on Sept. 19 for an interview in which she's expected to promote her book.