The Kremlin considers “ungrateful” to argue about the resignation of Pentagon chief James Mattis, said spokesperson for Russian President Dmitry Peskov.

His remark came in response to comment whether Mattis’ resignation in American politics will exacerbate unpredictability and strengthen the possibility of a radical foreign policy or not, RIA Novosti reported.

James Mattis has allegedly kept the US leader from many unpredictable steps, the source noted.

As reported earlier, James Mattis has resigned as Pentagon chief, referring to differences with the US President Donald Trump over the treatment of allies and the US approach to “malign actors and strategic competitors” on the world stage.