Sir Howard had an extensive judicial career in the UK and internationally, including serving as a judge at the International Criminal Tribunal for the former Yugoslavia (ICTY) and at the International Criminal Court (ICC) for over 12 years.

In this time, he served as a judge in a number of trials involving the most serious crimes of international concern, such as the case of Radovan Karadzic.

His appointment by Attorney General Suella Braverman QC MP comes after she signed a joint statement of support with Ukraine’s prosecutor general which reiterated the UK’s commitment to helping with the gathering of evidence of crimes which could include crimes against humanity and war crimes.

Ms Braverman said: “It has been a privilege to work with Ukraine’s prosecutor general, Iryna Venediktova, my admiration for her courage and determination grows with every meeting.

“The UK is committed to showing that the atrocities we see being committed day after day in Ukraine will not be forgotten and that those giving or following illegal orders will be tracked down and held to account.

“I am pleased to offer Sir Howard’s expert help and I will continue to do all I can as Attorney General to support Ukraine’s journey to justice against Russia.”

Ukrainian prosecutor general Iryna Venediktova added: “We are honoured to have Sir Howard Morrison’s help and I am grateful to the Attorney General for offering his assistance. Sir Howard’s experience and knowledge of international criminal law speaks louder than words and his help will be taken up immediately on a number of issues.”