Sir Keir Starmer warned his ministers they would “face consequences” if they fall short of the highest standards as he prepared to beef up the powers of his ethics tsar.

On his first day in office Sir Keir met the independent adviser on ministerial interests Sir Laurie Magnus in a sign that he will make improving standards in public life a high priority.

The Prime Minister confirmed he would enact a manifesto commitment to give Sir Laurie the powers to start his own investigations into allegations of ministerial wrongdoing, rather than wait for Sir Keir to decide whether to order one.

Sir Keir told reporters: “I did see Laurie on day one in Government to have a discussion with him about standards and the enforcement of standards.

“I do intend him to have an ability to investigate. You’ll have to forgive me, because I’m not quite sure whether that requires a formal change to the rules or not, but the intention is clear – whatever the technical way of doing it is, we’ll find a way to do it, so it’s not a reneging on that.”

Asked if ministers found to have broken the rules would be sacked “no ifs, no buts”, he said: “I made it clear – the ministerial code, they will be receiving a copy of it, and it will have the Nolan principles inside and alongside it.

“That is the standards I expect of them. As I’ve said throughout, people falling short of the required standards will face consequences, as you would expect.”

The Nolan principles of standards in public life are: selflessness, integrity, objectivity, accountability, openness, honesty and leadership.