Secretary of State Mike Pompeo unloaded on Friday on his Obama-era predecessor John Kerry for "actively undermining" US policy on Iran by meeting several times recently with the Iranian foreign minister, who was his main interlocutor in the Iran nuclear deal negotiations.

In unusually blunt and caustic language, Pompeo said Kerry's meetings with Mohammad Javad Zarif were "unseemly and unprecedented" and "beyond inappropriate." President Donald Trump had late on Thursday accused Kerry of holding "illegal meetings with the very hostile Iranian Regime, which can only serve to undercut our great work to the detriment of the American people."