Behaviour at the heart of government is under intense scrutiny after a series of scandals - including several illegal parties in Prime Minister Boris Johnson's offices during the COVID-19 lockdown.
The policy paper, published alongside the latest version of the Ministerial Code, said it was "disproportionate to expect that any breach, however minor, should lead automatically to resignation or dismissal".
It had previously been expected that ministers who breached the guidance would be dismissed, though the 2019 code itself did not set out sanctions, only stating ministers were expected to resign if they misled parliament.
While the prime minister may ask the Independent Adviser on Ministers' Interests, who advises him on the code, for guidance on the appropriate sanction for any breach, "the final decision rests with the Prime Minister," the updated code says.
"Where the Prime Minister retains his confidence in the Minister, available sanctions include requiring some form of public apology, remedial action, or removal of ministerial salary for a period," it said.
In a letter to Johnson in December, the current Independent Adviser, Christopher Geidt, called for his role to have "considerably greater authority, independence and effect" and criticised the fact that an exchange of messages had not been disclosed to him when investigating who funded a costly refurbishment of Johnson's Downing Street flat.
While the updated code says the adviser may now initiate an investigation, something previously only the prime minister could do, he is still required to consult the prime minister, "who will normally give his consent".
"Lord Geidt's independence has not increased. He still has to ask the PM for permission to investigate. Anything else is bluster," said Tim Durrant, Associate Director at the Institute for Government think tank.
(Reporting by Kylie MacLellan; editing by William James and Michael Holden)
