City solicitors must toughen up client due diligence or the profession will be hit by criminal sanctions for enabling kleptocrats to sluice ‘dirty money’ through London.

That is the stark message of a distinguished taskforce which was set up by the Institute of Business Ethics in the wake of Russia’s invasion of Ukraine to probe the role of solicitors in advising corrupt oligarchs.

Led by Guy Beringer, a former senior partner of Allen & Overy, the taskforce has recommended that law firms deploy a six-step ‘gating process’ for accepting clients to restore public trust. Complying with anti-money laundering regulations is not a sufficient safeguard, it said in a report this week.

Beringer warned at the report's launch on Wednesday that if solicitors continue to be viewed as facilitators of kleptocracy and corruption, politicians are ready to step in with legislation. Another taskforce member warned of the threat posed by Labour peer Baroness Hodge (Margaret Hodge), the UK’s recently appointed anti-corruption champion.

Hodge wants the government to introduce an offence holding lawyers criminally liable for failing to prevent economic crime.

Beringer stressed that solicitors have a ‘contract with the public’, which he said is a quid pro quo for their practising privileges and the profession’s barriers to entry.

‘That contract now needs to be taken out of the bottom drawer and reread,’ he added.

The institute is now seeking to establish a legal ethics forum.