Grouchy Rishi Sunak has refused to say whether he will order a probe into claims Suella Braverman tried to get civil servants help her avoid a speeding fine.
The PM also declined to say whether he had confidence in his Home Secretary in a tense exchange with journalists in Hiroshima, Japan.
He has been urged to order an investigation following claims Ms Braverman may have broken the ministerial code asking Home Office aides to arrange a one-to-one speeding course.
Speaking before heading home from the G7 summit in Japan, he tried to swerve questions about Ms Braverman's conduct.
He snapped at the BBC's Chris Mason, who tried to grill him on the reports: "Do you have any questions about the summit?"
When Mr Mason stood his ground, Mr Sunak said: "I don't know the full details of what's happened and nor have I spoken to the Home Secretary... but I understand that she has expressed regret for speeding, accepted the penalty and paid the fine."
He was then pressed by Sky News and ITV over whether it was appropriate for the Home Secretary to involve civil servants, but declined to comment further.
Questions on the matter are unlikely to go away, however, and the PM will arrive home to a fresh headache at the hands of Ms Braverman.
Following the exchange with reporters, Labour Shadow Home Secretary Yvette Cooper posted on Twitter: "The Home Secretary is alleged to have tried to abuse her position to avoid a legal penalty.
"This is a pathetic Government response. You promised integrity, professionalism & accountability
"Are you really too weak to even set up an investigation?"
And Lib Dem Home Affairs spokesman Alistair Carmichael accused the PM of stealing a page "from the Boris Johnson playbook".
He said: “By refusing to set up an investigation immediately, Rishi Sunak is stealing page one from the Boris Johnson playbook.
"Time and time again Sunak has put Conservative politicians, who think they are above the rules, in his cabinet and every time they have taken the British people for fools.
“The Home Secretary must undergo an urgent investigation, every second she doesn’t is another blow to the integrity of this already sleaze-ridden Prime Minister."
Ms Braverman allegedly requested that Home Office aides help organise a one-to-one driving awareness course after she was caught speeding last summer as she looked to swerve accepting points on her licence.
According to The Sunday Times, civil servants refused the request, leading Mrs Braverman to turn to a political aide to assist her in attempting to arrange an alternative to having to attend a course with other motorists.
The newspaper reported that a number of requests were made to a speeding awareness course provider by an aide, including asking if the senior Conservative minister would be able to undertake an online course, but be allowed to use an alias or have her camera switched off.
The suggestions were said to have been refused, with Mrs Braverman later choosing to forgo the course altogether and accepting three points on her driving licence.
Labour and the Liberal Democrats are calling for Mrs Braverman to face a probe by the Prime Minister's adviser on ministerial interests, Sir Laurie Magnus.
The rules currently mean that Rishi Sunak would have to commission his ethics tsar to look into the allegations, which Labour has suggested could breach the ministerial code - a set of rules all ministers must abide by or face sanctions, including potentially being sacked.
A source close to Mrs Braverman told PA news agency the speeding ticket and subsequent arrangements for dealing with it were reported to the Cabinet Office at the time.
They said the Home Secretary was keen to arrange a course, rather than take the points, due to concerns around her insurance premium potentially increasing.
Mrs Braverman was reportedly issued with a speeding notice by police after being caught driving faster than the speed limit on a road outside London when she was attorney general in the summer of 2022.
She was offered the choice of paying the fine and receiving three points, attending the course in lieu of points and the fine, or challenging the speeding notice.
The Sunday Times said it was after being appointed home secretary by former prime minister Liz Truss that she attempted to engage civil servants in the Home Office about trying to secure a special arrangement for a driving course.
Mrs Braverman resigned on October 19 as home secretary after sharing a sensitive document with a Tory backbencher from a personal email without permission.
She was, however, reappointed Home Secretary by Mr Sunak only six days later when he entered No 10.
It was at this point that she decided to drop her pursuit of a driving awareness course, instead taking the points, the newspaper reported.
Labour's Ms Cooper last night said the reports were "shocking".
She said: "As Home Secretary, Suella Braverman is responsible for upholding the law, yet this report suggests she has tried to abuse her position to get round the normal penalties so it is one rule for her and another for everyone else.
"We've had 13 years of the Tories trying to dodge the rules for themselves and their mates.
"Enough is enough. The Home Secretary and the Prime Minister need to both urgently explain what has been going on, including what the Prime Minister knew when he reappointed her.
"Rishi Sunak was too weak to deal with her the last time she broke the ministerial code, is he still too weak to take action now?
"The Prime Minister has promised integrity, professionalism and accountability, yet it appears his Home Secretary is blatantly flouting all three.
"We need an urgent investigation into what has gone on here, starting with Laurie Magnus seeing how this is possibly compatible with the ministerial code."
