Pete Hegseth, the US secretary of defence, has cut the pension and demoted the rank of a Democrat who appeared to criticise the military’s actions under his leadership.

Mark Kelly, a US senator for Arizona and a retired Navy captain, appeared in a video alongside several other Democrats with military backgrounds, urging troops to refuse “illegal orders”.

“Our laws are clear,” Mr Kelly said in the video published on Nov 18. “You can refuse illegal orders.”

The footage was circulated amid intense questioning over the legality of US military strikes on alleged drug trafficking boats in the Caribbean, part of Donald Trump’s efforts to oust Nicolas Maduro.

Mr Maduro has since been captured and charged with drug offences.

Mr Hegseth announced on Monday that Mr Kelly’s rank would also be demoted. He accused the Arizona senator of “reckless misconduct” and said that the video was “clearly intended to undermine good order and military discipline”.

Mr Hegseth, whose department has informally been renamed the “department of war” also threatened further action against Mr Kelly.

In response, Mr Kelly said he would “fight this with everything I’ve got.”

“Pete Hegseth wants to send the message to every single retired service member that if they say something he or Donald Trump doesn’t like, they will come after them the same way. It’s outrageous and it is wrong. There is nothing more un-American than that,” Mr Kelly said in a statement on X.

The censure of Mr Kelly stops short of the threat previously made by the administration to recall him to active military duty status to prosecute him, after what the Trump administration described as seditious behaviour.

Mr Hegseth said Mr Kelly has 30 days to respond and that the administrative process would conclude 15 days later.

“Captain Kelly’s status as a sitting United States senator does not exempt him from accountability, and further violations could result in further action,” Mr Hegseth added.

Mr Kelly and the other Democrat politicians in the video, including Elissa Slotkin, Jason Crow, Maggie Goodlander, Chris Deluzio and Chrissy Houlahan, have defended their remarks, saying they were merely stating what US law requires of troops if they are given an unlawful order.

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