Bernie Sanders, Elizabeth Warren and Tammy Baldwin want BlackRock CEO Larry Fink to get his hands dirty and broker a deal with striking workers at Warrior Met Coal.

Sens. Bernie Sanders, Elizabeth Warren and Tammy Baldwin want BlackRock  (BLK) – Get BlackRock, Inc. Report CEO Larry Fink to get his hands dirty, at least proverbially.

The trio are pressing the Wall Street private equity titan to use his firm’s sizeable financial stake in Warrior Met Coal  (HCC) – Get Warrior Met Coal, Inc. Report to compel the company’s management to broker a deal with its striking coal miners.

“As we hope you understand, the mines in Alabama run 24 hours per day. Workers can face termination for missing more than four days of work,” Sanders, Warren and Baldwin wrote in a letter dated Thursday that was obtained by CNBC.

“Mr. Fink: Our request to you is simple,” Sanders, Warren and Baldwin added. “BlackRock’s Board must publicly demand that Warrior Met negotiate in good faith and agree to a reasonable contract that treats workers with dignity and respect.”

“Given BlackRock’s stake in the company and your position within BlackRock, we are asking you to do the right thing.”

BlackRock is scheduled to publish its quarterly earnings report later Friday morning that among other things is expected to reinforce what the asset management giant spelled out in its 2020 letter: its commitment to ESG and sustainability, as well as its pivot away from investing in coal.

Thermal coal is “…significantly carbon intensive, becoming less and less economically viable, and highly exposed to regulation because of its environmental impacts,” last year’s letter said.

“With the acceleration of the global energy transition, we do not believe that the long-term economic or investment rationale justifies continued investment in this sector.”