In a report published today, the committee has emphasised that as the cabinet manual is now a decade old, it needs to be updated or risk becoming moribund.

The report explores the process of updating the manual, how Parliament should be involved and what role the manual should play as a public document.

It highlights that documents such as the cabinet manual, the ministerial code and the civil service code are an important part of the UK’s constitutional framework and that together with the Nolan Principles, respect for the manual and codes is essential for upholding principles of good governance, including adherence to constitutional conventions and the proper conduct of public and political life.

The report has also recommended that the prime minister makes clear, in the foreword to the next edition, the duty on all ministers to adhere to important ethical and constitutional principles in the cabinet manual.

Baroness Taylor, chair of the Constitution Committee, said: “Since the publication of the first manual in 2011 there have been significant developments in relation to Brexit and devolution, as well as the anticipated repeal of the Fixed-term Parliaments Act. We therefore decided to conduct a short inquiry into whether the manual needs to be updated and what role it should play as a public facing document.

“We have previously recommended that the manual be regularly updated, with any revisions reflected immediately in the online version. In response to the evidence, we received during our inquiry, we recommend that any updates to the cabinet manual should as a matter of routine be considered at the beginning of each Parliament and endorsed by the cabinet. As with the first edition, this process should include consulting parliamentary committees, academics and the public on a draft version.

“However, as an update to the manual is now well overdue, we recommend a draft update should be issued within the next 12 months, in advance of the next general election.

“The manual and the associated codes are crucial to maintaining the public’s trust in government. They must never be treated as optional extras to be swept aside or ignored to suit the convenience of the executive.”