AFP via Getty ImagesThe Iranian and Russian regimes are "brothers in hatred", Volodymyr Zelensky has told MPs and peers, as he warned about the dangers of drone warfare.
Addressing around 120 parliamentarians in a Westminster committee room, the Ukrainian president highlighted how Tehran was selling Shahed 'kamikaze' drones to Moscow, which had been used in Ukraine.
He also warned against easing sanctions on Russian oil, saying it was "crucial" to keep up the pressure against Moscow.
The US has temporarily eased sanctions on some Russian oil in an attempt to tackle surging prices triggered by the conflict in the Middle East.
Among those in the audience in a packed committee room were Prime Minister Sir Keir Starmer, Nato secretary-general Mark Rutte, Defence Secretary John Healey and leaders of opposition parties.
In his speech, Zelensky sought to link the headline-generating war in the Middle East with the long-running conflict in Ukraine.
He argued that Ukrainians were now pioneers in modern warfare and schooled in techniques they could share with allies.
In its fight against Russia, Ukraine has been using cheap, mass-produced interceptor drones to defend its skies.
Zelensky said there were now 201 Ukrainian military experts in the Middle East, with another 44 ready to deploy, who were sharing their knowledge on how to defend against Iranian drones.
He added that Ukraine was "ready to offer similar deals to all our reliable partners".
On a TV screen, Zelensky demonstrated how Ukraine was mapping Russian strikes and defensive action against them in real time.
He explained how using technology as simple as an iPad allowed Ukrainian commanders to control the country's security.
Zelensky added that during a meeting earlier at Buckingham Palace, he gave the King the iPad "as a sign of respect and gratitude", to "strengthen our cooperation with the United Kingdom".
PA MediaThe Ukrainian leader met the monarch ahead of his speech Earlier, Sir Keir said "the focus must remain on Ukraine" despite the Iran war, ahead of a meeting with Zelensky.
Welcoming the Ukrainian leader to No 10, the prime minister said: "Putin can't be the one who benefits from a conflict in Iran, whether that's oil prices or the dropping of sanctions."
During their meeting, the leaders agreed a new defence partnership aimed at tackling cheap attack drones.
Downing Street said the deal would bring together "Ukrainian expertise and the UK's industrial base" to manufacture and supply drones and other capabilities.
Under the partnership between the UK and Ukraine, closer co-operation in the defence industries will also be sought with third countries as part of efforts to bolster international security.
Britain will also give £500,000 to fund an AI centre of excellence in Kyiv.
It comes as the US-Israeli war with Iran enters a third week, while US President Donald Trump continues to criticise the UK and other countries over the extent of their response to the conflict.
Rising oil prices are fuelling Russia's war machine, while Ukraine's allies are distracted and divided over the Middle East.
Zelensky is currently on a tour of European capitals to shore up support and keep his conflict at the forefront of allies' minds.
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War in UkraineVolodymyr ZelenskyKeir StarmerUkraine
