The group is composed of constitutional experts including former permanent secretaries of the civil service, professors of public law and a former lord chief justice of England and Wales.

In a report covering the first seven months of 2022, the UKCMG highlighted almost 90 instances where constitutional norms of the United Kingdom had been degraded or eroded. While some of the issues identified pre-dated the Johnston administration, the report found that Johnson’s government had frequently exploited and worsened them.

Revelations of failures to adhere to basic norms of conduct among ministers and civil servants, a raft of ill-considered constitutional legislation and attacks on the independence of the judiciary all contributed to a decline in the strength of the UK constitution. The report calls for greater integrity and a return to standards in public life.

The UKCMG now warns that unless action is taken by the new prime minister the damage to the constitution could threaten the shape and quality of democracy in the United Kingdom.

The editor of the report, Professor Andrew Blick of King’s College, University of London said: “The latest report of the UKCMG has identified several areas of profound concern which have jeopardised the constitutional stability of the United Kingdom.

“The seven months from January to the end of July of this year saw the exposure and worsening of existing frailties in our constitution. These frailties now offer a serious threat to the strength and shape of UK democracy unless urgent action is taken.”