Roger Stone – a former advisor to Donald Trump – has been gagged by a judge after he admitted posting an image on social media that showed her next to a set of cross-hairs.

The 66-year-old veteran political operative and celebrated enforcer of dirty drinks, told the judge he acted in error when he posted the image.

He asked her not to alter his bail conditions relating to charges brought by special counsel Robert Mueller, saying: “I am kicking myself over my own stupidity.”

But federal judge Amy Berman Jackson, deciding what sanction should be imposed on Mr Stone, said she was not taken in by his appeals.

She said he would “pose a danger” to others in the case unless she modified the terms of his release to include the gag order. While she decided he did not need to go to jail, she warned him he would be sent there if he broke the rules again.

“So no, Mr Stone, I’m not giving you another chance. I have serious doubts about whether you’ve learned any lesson at all.”

The man said to have invented the phrase “rat-f***ing” in relation to political skullduggery, was obliged to appear before Ms Jackson when he was arrested last month by FBI agents after being indicted by Mr Mueller’s team with seven charges.

He has denied allegations that he lied to congress and obstructed the House of Representative’s intelligence committee’s investigation of Russia’s alleged interference in the 2016 election, and possible collusion with the Trump campaign.

When he secured $250,000 bail over the charges, one of the conditions was that he not talk about the case.

Yet, Mr Stone has made numerous media appearances since his arrest. Reuters said that last week, Ms Jackson prohibited Mr Stone or his lawyers from speaking with the news media or making statements near the federal courthouse about the case, in order to reduce the risk of tainting the jury pool and harming his right to a fair trial.

But just days later, he posted a photograph of Ms Jackson next to the image that looked like crosshairs. He later took down that version and reposted it without the crosshairs, before taking down the post a second time.

“How hard was it to come up with a photo that didn’t have the crosshairs in the corner?” Ms Jackson asked Mr Stone, the news agency said.

Mr Stone said he had asked a volunteer to provide him with a photo and said he did not review it ahead of time. “I didn’t even recognise it was crosshairs ... Until it was brought to my attention by a reporter.”