Jamie Briggs' resignation from the junior ministry after an incident with a public servant in a Hong Kong bar is being mourned by few of his colleagues, with Nationals senator John Williams saying his departure will only improve the quality of the ministry.

The Member for Mayo sensationally revealed he was quitting over the incident which occurred late at night at the end of last month, in a well known Hong Kong bar during his visit as Cities Minister at the end of November.

Senator Williams told Fairfax Media that Mr Briggs resignation would be no loss.

"With Briggs leaving it means there will be no deterioration in the overall quality of the ministry, in fact it should improve," Senator Williams said on Tuesday.

News of the resignation came just minutes before Prime Minister Malcolm Turnbull announced another member of his ministry - Special Minister of State Mal Brough - would be stepping down.

One Liberal who did not wish to be named said Mr Turnbull had removed two of the Ministry's most internally loathed members: "The IQ quota has gone up and the talentless arrogance quota has gone down with this move," the Liberal said.

Speaking in his home town of Adelaide, Mr Briggs said the incident occurred on a recent official trip to Hong Kong when he invited the woman and several other officials out to a private dinner.

The minister said he invited the woman out for drinks to a "popular, and as it transpired, very crowded bar," with his Chief of Staff Stuart Eaton.

Mr Briggs said their interactions at the bar were informal but, in the days after, the public servant made a complaint about his behaviour towards her.

"At no point was it my intention to act inappropriately and I'm obliged to note for the record that nothing illegal has been alleged," Mr Briggs told reporters.

Mr Briggs described it as an "error of professional judgement".

"There was offence taken by this public servant, after the event. [It was] raised with me, I've apologised to her," he said.

Mr Briggs said he had discussed the matter with Mr Turnbull, who told him that his behaviour failed the standard he expects of his ministers and invited him to "reflect on his position."

"After careful reflection about the concerns she raised, and the fact that I was at a bar late at night while on an overseas visit, I've concluded that this behaviour has not met the particularly high standards for ministers. Therefore the proper course of action for me is to resign," Mr Briggs said.

He said he was not naming the public servant at her request to protect her privacy. He said it was a "difficult day" for himself personally and his family and also his staff.

"It's a difficult day for several staff who also [will] lose their jobs because of these actions," Mr Briggs said.

Mr Briggs was almost dumped from the Ministry in September after Mr Turnbull's Cabinet reshuffle, where he was handed the Cities and Built Environment portfolio. He was previously the Assistant Minister for Infrastructure and Regional Development.

He said he would recontest the seat of Mayo at the 2016 federal election and hoped one day to return to the ministry.

"I intend to again one day to have those opportunities to serve at the higher level," he said.

In a statement issued a short time later, Mr Turnbull did not rule out Mr Briggs returning to the frontbench.

"While disappointed by the conduct that led to his resignation, I thank Mr Briggs for his capable service as a minister," Mr Turnbull said.

"I look forward to Mr Briggs continuing to make a valuable contribution to the work of the government in the future."

Environment Minister Greg Hunt will take on Mr Briggs' ministerial duties for Cities and the Built Environment.

A number of MPs tweeted their support of Mr Briggs, including Finance Minister Mathias Cormann who will temporarily become the Special Minister of state in place of Mr Brough, and Queensland liberal MP Ewen Jones.

smh.com.au