The enemy of my enemy …

US Sens. Bernie Sanders and Elizabeth Warren found common ground in South Carolina — the need to narrow the lead of presidential rival Joe Biden — and shook on it Monday.

The two leading progressives put their differences aside for a morning of campaigning in the state, where the former veep holds a 17-point lead in the 2020 Democratic race, to engage in a hand-grasp heard around the country.

Warren of Massachusetts was in the front row of Zion Baptist Church in Columbia for the state’s largest celebration of Martin Luther King Jr. Day when she reached out her hand to Sanders as he walked to his seat in the same row.

The Democratic socialist from Vermont quickly shook Warren’s hand before greeting nearby US Rep. Tulsi Gabbard (D-Hawaii), a longtime ally, with a hug.

US Sen. Amy Klobuchar (D-Minn.), also a Democratic presidential contender, was on hand to witness the significant greeting, too.

“This is THE handshake,” Gabbard was heard saying after the exchange, likely a reference to Warren’s refusal to shake Sanders’ hand after last week’s debate.

During the televised sparring, Warren and Sanders squabbled over whether he had previously told her that he did not believe a woman could win the presidency in 2020, as she had alleged.

Sanders denied the claim.

As other candidates shook hands at the end of the program, the cameras caught Warren rejecting a handshake from Sanders — and then a tense conversation between the two.

A hot mic unearthed by CNN revealed that during the discussion, Warren accused Sanders of calling her a liar on national television.

Sanders could later be heard accusing Warren of calling him a liar before they agreed to continue the discussion another time.

In an even greater show of unity after their handshake Monday, the two senators linked arms as they participated in a march through downtown streets to the statehouse, where a rally was held in King’s honor.

Onlookers noted that the two appeared fairly friendly to one another during the march — when they weren’t busy singing along to “We Shall Overcome” for part of the six-block trip.

But Warren looked much more chummy with Klobuchar, who was linked to her other arm.

Other Dem candidates such as Biden, former South Bend, Ind., Mayor Pete Buttigieg, Tom Steyer and former Massachusetts Gov. Deval Patrick were also in attendance.

Biden has held steady in the polls for months in South Carolina, the South’s first primary.

The former veep comfortably leads the state’s primary with 32 percent of support, according to a Real Clear Politics average. Sanders and Warren trail behind, with 15 and 14 percent, respectively.