Justice ministers from around the world will meet in London on Monday to discuss scaling up support for the International Criminal Court after it issued an arrest warrant last week for Russian President Vladimir Putin.
The ICC accused Putin of the war crime of illegally deporting hundreds of children from Ukraine. Moscow rejects the charges, calling the move unacceptable and saying it has no legal force in Russia which is not an ICC member.
"We are gathering in London today united by one cause: to hold war criminals to account for the atrocities committed in Ukraine during this unjust, unprovoked and unlawful invasion," British Deputy Prime Minister Dominic Raab said.
"The UK, alongside the international community, will continue to provide the International Criminal Court with the funding, people and expertise to ensure justice is served."
Britain has pledged GBP 1 million ($1.22 million) to the ICC this year and the justice ministry said other countries were expected to pledge financial support during the conference in London, which will be co-hosted by Britain and the Netherlands.
The funding will go towards training for investigators to examine alleged war crimes, as well as psychological and practical support for victims, the ministry said.