Former Senator Joe Lieberman criticized John Kerry on Sunday for engaging in shadow diplomacy to try to save the Iran Deal.

WATCH:

A new Boston Globe report explained that Kerry, former secretary of state, has been using contacts he developed at the State Department to meet with foreign leaders who are favorable to the Iran Deal. Kerry’s moves fly in the face of official American foreign policy, as the Trump administration has expressed desires to back out of the deal. (RELATED: Report: John Kerry Colludes With Iran To Undermine American Foreign Policy)

During an interview with Fox News’ Maria Bartiromo, Lieberman said Kerry is acting inappropriately by negotiating without being in an official government position.

“John Kerry is not negotiating on behalf of the U.S. government — I hope everybody he’s talking to knows that,” Lieberman said. “But, in my opinion, what he’s doing is inappropriate and he shouldn’t be doing it.”

Lieberman noted that Kerry is being uniquely uncouth because former secretaries of state Condoleezza Rice and Hillary Clinton haven’t gone around talking to the Iranians or Europeans since leaving office.

“[The Trump administration] is a duly elected administration so I hope John Kerry stops,” Lieberman concluded.

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