British Prime Minister Rishi Sunak has upheld the UK’s long-standing position on cluster munitions, making it clear that his government discourages their use.
He spoke after the US said it would send cluster bombs to Ukraine as part of a new push to support the country’s counter-offensive against Russian forces.
Mr Sunak, who is due to welcome US President Joe Biden to Downing Street for talks on Monday, chose not to back the donation.
His disapproval came hours after Mr Biden said it was a “difficult decision” to send the explosives, but “the Ukrainians are running out of ammunition”.
“The UK is signatory to a convention which prohibits the production or use of cluster munitions and discourages their use,” Mr Sunak said.
The UK is one of 123 signatories of the Convention on Cluster Munitions, an international treaty that prohibits all use, transfer, production and stockpiling of the bombs.
Mr Sunak stressed that Britain is supporting Kyiv by providing tanks and long-range weapons.
“We will continue to do our part to support Ukraine against Russia’s illegal and unprovoked invasion," he said.
"But we’ve done that by providing heavy battle tanks and most recently long-range weapons, and hopefully all countries can continue to support Ukraine."
“Russia’s act of barbarism is causing untold suffering to millions of people.
“It’s right that we collectively stand up to it and I’ll be heading off to the Nato summit next week in Vilnius, where we will be discussing exactly this with our allies, how we can strengthen our support for Ukraine.”
Mr Sunak was speaking during a by-election campaign stop in Selby.
The US says that Kyiv will use the cluster bombs carefully, and they will not be used in urban areas.
Many of Washington’s Nato allies have banned the use of cluster munitions due to their record of killing civilians.
America’s fellow members in the trans-Atlantic alliance are likely to be uneasy over the transfer, and the topic is bound to feature at next week's summit in Vilnius.
The weapons scatter a large number of bomblets across a wide area.
Unexploded bomblets can continue to pose a threat to civilians long after conflicts end.
Ukrainian President Volodymyr Zelenskyy thanked the US for the “timely, broad and much-needed defence aid package” that will “bring Ukraine closer to victory over the enemy, and democracy to victory over dictatorship”.
Mr Biden is expected to touch down in Britain on Sunday evening and hold talks with Mr Sunak at No 10 on Monday. He will also travel to Windsor Castle for an audience with King Charles III.