Police will not be taking further action over remarks made by Nigel Farage at a rally in which he told the crowd “once Brexit is done, we will take the knife” to “overpaid pen-pushers in Whitehall.”

Gwent police said they were looking into the comments made by the Brexit party leader during the event at the Neon in Newport last weekend. The comments, made to an audience of about 500 people, were reported to the force by several people on Twitter.

The force later issued a statement saying: “We are aware of the heightened tensions that exist regarding use of language, and take all allegations and concerns from members of the public very seriously.

“However, following a thorough assessment, it is our view that the comments in the video, do not constitute a criminal offence. As such, Gwent police will not be taking any further action.”

Naomi Long, an MEP for the Alliance party, had asked police on Twitter if they would be investigating “this clear case of incitement to violence against staff in the civil service”.

Farage has since claimed he was talking about reducing the number of civil service jobs after Brexit. He tweeted: “I should have said ‘take the axe’, which is a more traditional term for cuts.”

I should have said ‘take the axe’, which is a more traditional term for cuts. https://t.co/3SCyut3tlx — Nigel Farage (@Nigel_Farage) September 28, 2019

During the speech, Farage also described his opinion of several political figures including “that ghastly little man called [John] Bercow” and “that perfectly vile little pipsqueak of a prime minister in Luxembourg”.

It comes after Boris Johnson triggered widespread criticism over his inflammatory rhetoric in the Commons on Wednesday.

The prime minister told the Labour MP Paula Sherriff, who disclosed she received death threats every day, that her concerns about his language fuelling violence were “humbug”. Johnson also said the best way to honour the murdered MP Jo Cox was to “get Brexit done”.

Johnson declined to apologise for his remarks about Cox and did not attend a Commons debate on incendiary rhetoric. But he later acknowledged the need to moderate violent language on all sides of the debate.

The prime minister was reported to have told Conservative MPs on Thursday that he would continue to use his language about the so-called Benn act to stop a no-deal Brexit. He had labelled the legislation the “surrender bill”, despite criticism that this depicts his opponents in parliament as traitors guilty of a betrayal.

Johnson was criticised by his sister, Rachel, who told Sky: “I do think it was particularly tasteless for those grieving a mother, MP and friend to say the best way to honour her memory is to deliver the thing she and her family campaigned against.

“I think it was a very tasteless way of referring to the memory of a murdered MP, murdered by someone who said ‘Britain first’, of the far-right tendency, which you could argue is being whipped up by this sort of language.

“My brother is using words like surrender and capitulation as if the people standing in the way of the blessed will of the people as defined by 17.4m votes in 2016 should be hung, drawn, quartered, tarred and feathered. I think that is highly reprehensible language to use.”

The former home secretary Amber Rudd accused Johnson of inciting violence for using words such as “surrender” and accusing MPs of “betraying” the people.

The Church of England’s bishops released a joint statement on Friday, calling on people both inside and outside parliament to treat each other with greater respect. They spoke after numerous MPs complained of receiving threats and Johnson’s senior aide, Dominic Cummings, suggested that only carrying out Brexit would ease tensions. “In the last few days, the use of language, both in debates and outside parliament, has been unacceptable,” the bishops wrote.