Sir Philip Pullman has denied advocating the hanging of Boris Johnson after being widely criticised for a tweet about the prime minister.
The author said in a since-deleted post on Twitter that he thinks of a “rope” and “the nearest lamp-post” when he hears Mr Johnson’s name.
After being met with a backlash on Thursday, Sir Philip said he had made a “tactical error” but refused to apologise for his anger at the PM’s decision to suspend parliament.
In the original tweet, Sir Philip, 72, said: “When I hear the name ‘Boris Johnson’, for some reason the words ‘rope’ and ‘nearest lamp-post’ come to mind as well.”
Following criticism online, the Northern Lights author blamed recent political events for his post and said he wanted to make it “perfectly clear” that he did not want to kill Mr Johnson.
Sir Philip said: “I’ve deleted a tweet which apparently upset a lot of people. I don’t advocate hanging Boris Johnson. I think that would be a very bad idea.
“Recent events have aroused my anger to the point where I temporarily lost my judgment. In the heat of the moment I made a tactical error.
“Johnson’s attempt to silence parliament is a low point in our nation’s political history. It was not my aim to distract from the genuine and legitimate outrage of many people at this, and I’m sorry it happened.
“Freedom of speech, like freedom of assembly, is precious. So is life.
“Just to make it perfectly clear: I wouldn’t kill the prime minister, and I don’t want anyone else to. But I don’t apologise for the anger I feel; only for its intemperate expression.”
Conservative MP Robert Courts criticised Sir Philip, writing on Twitter: “You always know people have lost the argument & have little intellectual confidence in their case when they resort to hideous language & sick personal abuse like this.”
Fans of the author had also urged him to delete the post.
In a message to Sir Philip, Liberal Democrat MP Sarah Wollaston wrote on Twitter: “No one should give a scrap of incitement to violence, especially those with great influence. You should delete.”
Author Emma Kennedy tweeted: “Philip, you’re my hero, but that tweet will be reported and you’ll be banned and that would be the absolute last thing we all need. So pause and perhaps think about deleting?”
Sir Philip’s latest controversial tweets follow a post on Wednesday in which he called Mr Johnson a dictator, adding: “We must get rid of him and his loathsome gang as soon and as finally as possible.”
Mr Johnson has said he wants to prorogue parliament in order to bring the current record-breaking session to a close and work on his government’s new legislative agenda.
But the decision has provoked strong reactions, with opposition leaders accusing the PM of trying to halt their efforts to block a no-deal Brexit.
There was fierce criticism online after a Twitter user posted the home address of Commons leader Jacob Rees-Mogg and called for a protest outside the property.
LBC presenter James O’Brien, who had retweeted the post to condemn it, later wrote: “Deleted my last tweet because even a condemnation entails promotion of sorts.
“Don’t arrange protests at politicians’ homes. You can’t guarantee they’ll be peaceful & other people usually live there.”
It comes a day after actor Hugh Grant launched a foul-mouthed tirade against Mr Johnson on Twitter after the PM’s decision to suspend parliament.
Grant tweeted: “You will not f*** with my children’s future. You will not destroy the freedoms my grandfather fought two world wars to defend.”
He also claimed Britain was “revolted” by Mr Johnson.