CABINET Office minister Sir Gavin Williamson says he “regrets” the language used in a series of abusive text messages to another MP. 

However, one of his frontbench colleagues claimed a number of people had a "difficult relationship" with the women targeted.

Speaking to Sky News, Oliver Dowden also insisted Rishi Sunak still had confidence in the minister.

In a series of texts, obtained by the Sunday Times, Sir Gavin, accused Wendy Morton, who was chief whip at the time, of using the death of the monarch to “punish” senior MPs who were out of favour with Liz Truss’s government.

The paper said the then party chairman, Sir Jake Berry, informed Prime Minister Rishi Sunak the day before he entered No 10 that Ms Morton had submitted a formal complaint to the party about Sir Gavin’s conduct.

Both Sir Jake and Ms Morton lost their jobs in the ensuing reshuffle while Sir Gavin – a former chief whip and a supporter of Mr Sunak – returned to government.

In the messages, Sir Gavin said it was “very poor” that privy councillors who “aren’t favoured” by Ms Truss had been excluded from the funeral at Westminster Abbey.

Ms Morton said the claims were unfounded and that the government only had an “extremely limited” number of tickets.

Mr Williamson retorted: “Well certainly looks it which think is very shit and perception becomes reality. Also don’t forget I know how this works so don’t puss (sic) me about.

“It’s very clear how you are going to treat a number of us which is very stupid and you are showing f*** all interest in pulling things together.

“Also this shows exactly how you have rigged it is is (sic) disgusting you are using her death to punish people who are just supportive, absolutely disgusting.”

“Well let’s see how many more times you f*** us all over. There is a price for everything.”

Sir Jake told the paper that he was informed by the Conservative Party chief executive on October 24 that a complaint had been made against Sir Gavin regarding allegations of “bullying and intimidation of parliamentary colleagues”.

“In compliance with protocol, in my capacity as party chairman, I informed both the new Prime Minister and his incoming chief of staff about the complaint on the same day,” he said.

According to The Sunday Times, Mr Sunak did not recall the “specifics” of their conversation.

Sir Gavin told The Sunday Times: “I of course regret getting frustrated about the way colleagues and I felt we were being treated.

“I am happy to speak with Wendy and I hope to work positively with her in the future as I have in the past.”

Speaking on Sky News’s Sophy Ridge, Oliver Dowden, the Chancellor of the Duchy of Lancaster, confirmed that Mr Sunak had been aware of the complaint when he made Sir Gavin a Cabinet Office minister.

He said: “Well, the Prime Minister knew that there was a difficult relationship. As you have seen from the former chairman Jake Berry, he says that he highlighted that to the Prime Minister.

“But in terms of the specific allegations, the specific exchange, the Prime Minister wasn’t aware of it until last night.”

Mr Dowden continued: "He shouldn't have sent those messages. And he says that he regrets it. But of course, the prime minister continues to have confidence in Gavin Williamson as minister."

He later told the BBC's Laura Kuenssberg show: "It was no secret that Gavin Williamson, and others indeed, didn't enjoy a good relationship with the chief whip at the time."

Labour's Ed Miliband described the matter as "incredibly serious" and says it "calls into question, Rishi Sunak's judgement and the way he made decisions about his cabinet".

"We already know about the whole Suella Braverman issue being reappointed six days after she resigned," he said.

"It was very noticeable on your show that Oliver Dowden couldn't deny that Rishi Sunak knew about those issues to do with potential bullying against Wendy Morton, the chief whip, by Gavin Williamson - and yet he reappointed him.

"What it says is that Rishi Sunak was making decisions simply in his own narrow, short term interests as far as the Conservative Party leadership was concerned, not the national interest.

"And there needs to be an urgent independent investigation into exactly what happened. We can't have a cover up. We can't have a whitewash here. What did she do not know when it you know it? What did Gavin Williamson do? And what are the implications of that?"