The new digital trade agreement will be signed in London on Wednesday by Trade Secretary Kemi Badenoch and Ukraine’s First Deputy Prime Minister, Yulia Svyrydenko.
Based on a similar agreement this year between the UK and Singapore, the deal will support digital commerce through cross-border data flows, officials said.
It follows an approach by the government in Kyiv over the summer to see if such an agreement would be possible.
Digital trade is considered to be particularly important in the conflict with Russia, where the fighting and the damage to infrastructure makes physical trade more difficult.
The agreement also allows for greater co-operation between the UK and Ukraine on cyber security and emerging technology.
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“The landmark digital trade deal agreed today between our two countries paves the way for a new era of modern trade between us," Ms Badenoch said.
“This agreement will mean our businesses and governments can collaborate even more and ensure Ukrainians have access to essential goods and services as digital trade opens up.
“This will help protect jobs, livelihoods and families now and in Ukraine’s post-war future.”