A second Kent MP has resigned from the role in government.
Faversham and Mid Kent MP Helen Whately announced her decision on Twitter this morning.
Ms Whately said she regretted having to resign but said that there “are only so many times you can apologise and move on.”
She worked alongside the former Chancellor Rishi Sunak as Exchequer secretary to the Treasury.
In her own resignation letter, Mrs Whately said: “Your vision for our country and your mission to level up has galvanised and inspired our country. As exchequer secretary I have seen this in practice and been proud to play a part.
"I have argued that you should continue as Prime Minister many times in recent months but there are only so many times you can apologise and move on. That point has been reached.”
The MP was a care minister prior to joining the Treasury and was considered a party loyalist.
Her decision came within moment of Brandon Lewis resigning as Northern Ireland - becoming the fourth cabinet member to step down in 48 hours.
The resignations so far today include:
Analysis from Paul Francis
After a tumultuous 24 hours which saw the Prime Minister's authority ebbing away, there is a political deadlock that no-one seems to know how to break.
The Prime Minister insists he has a mandate from voters to continue in in the job; his former cabinet colleagues insist that he has no such mandate from the parliamentary party and that is what counts.
We are in uncharted political waters that are getting choppier by the hour.
Just how the crisis can be resolved is unclear. Even if MPs change the rules to allow a second vote of no confidence, that may not happen for a few days meaning greater uncertainty and political turbulence.
A busy day in government yesterday began with Sevenoaks MP Laura Trott announcing her resignation from her role in the department for transport.
By the end of the day 46 members had done the same and at the end of the day Mr Johnson dramatically sacked Micheal.
Mr Gove is thought to have told the Prime Minister that it was time for him to go.
The mass exodus began on Tuesday evening when health Secretary Sajid Javid and Chancellor Rishi Sunak said they could no longer continue at around 6pm on Tuesday.
Mr Javid said: "It has been an enormous privilege to serve in this role, but I regret that I can no longer continue in good conscience."
He added: "I served for you loyally and as your friend. We all serve the country first. When made to choose between those loyalties there can be only one answer."
Chancellor Rishi Sunak then resigned saying: "The public rightly expect government to be conducted properly, competently and seriously. I recognise this may be my last ministerial job, but I believe these standards are worth fighting for and that is why I am resigning."
But Liz Truss then said she was "100% behind" Mr Johnson, Nadine Dorries said she was staying and so did Jacob Rees-Mogg.
Mr Johnson at first said he knew nothing of previous claims against Mr Pincher.
The MP has now been suspended and resigned from his post after being accused of groping two men at the Carlton Club – a private members' club popular with Tory politicians – last week.
He's said to have been so drunk he couldn't remember his address and was bundled into a taxi at 1am, handing in his resignation the following day and saying he "drank too much".
In the wake of that incident it has transpired Mr Johnson was aware of past allegations of improper conduct levelled at Mr Pincher but appointed him anyway.
Downing Street at first denied he knew anything before saying he didn't know about any "specific incidents" but was aware of new reports and "unsubstantiated" claims.
But earlier a cabinet minister said the PM "forgot" he'd been told about an upheld complaint against Mr Pincher in 2019.
It's the latest scandal to rock the PM's tenure.
He seemed to have weathered the Partygate storm and previous issues around Owen Paterson and revamping his Downing Street flat.