Aysu Bicer
23 June 2025•Update: 23 June 2025
LONDON
UK’s Foreign Secretary David Lammy has warned Iran against retaliation after US strikes targeted three of its nuclear facilities over the weekend, urging Tehran to return to diplomacy and avoid what he described as a "catastrophic mistake."
In an interview with BBC on Monday, Lammy confirmed he had spoken directly with Iran’s foreign minister, delivering a stark message amid rising regional tensions.
"I told Iran that it would be a catastrophic mistake for them to retaliate by firing at US bases, or by blockading the key shipping lane of the Strait of Hormuz," Lammy said.
His comments came as Iran vowed "everlasting consequences" in response to Saturday night’s strikes on its nuclear sites at Natanz, Isfahan and Fordo — an operation carried out by the US in what it described as an effort to degrade Iran’s capacity to enrich uranium.
While Washington has defended the strikes as necessary to prevent Tehran from crossing nuclear red lines, the UK has sought to distance itself from the operation.
On Sunday, UK Prime Minister Keir Starmer said his country was not involved in the military action and stressed the need to prevent escalation.
Lammy echoed that call for restraint but acknowledged growing frustration with Iran’s nuclear ambitions.
"They have to get serious about the off-ramp that is being made available to them," Lammy said. "There is still an off-ramp and I was discussing that with the Iranian foreign minister again on the phone yesterday."
He noted that the UK, alongside its allies in the G7, the EU, and the Arab world, is urging Iran to reengage in nuclear talks with the so-called E3 — the UK, France and Germany — as well as with the US.
"We, alongside all of our partners in the G7, across Europe and across the Arab world and the Levant, are urging the Iranians to get serious both with the E3 — us, Germany and France — but also with the United States," Lammy said.
‘I don't say it's not legitimate’
Pressed on whether the US strikes were legal under international law, Lammy said: "I don't say it's not legitimate," but argued that the situation could not be equated with Russia's war on Ukraine.
Acknowledging the failure of diplomacy so far to curb Iran’s nuclear program, Lammy said: "Clearly it was not working."
"The International Atomic Energy Agency (IAEA) had confirmed the 60% enrichment and the Iranians were still obfuscating and engaged in deception," he added.
The enrichment of uranium to 60% purity is widely viewed by Western governments as a step toward weapons-grade material, though Tehran insists its nuclear program is for peaceful purposes.
"If Iran obtained nuclear weapons, there was likely to be nuclear proliferation across the Middle East, the world would be seriously more dangerous, and that's why it must be stopped," Lammy said.
He reiterated that while Iran has the right to a civilian nuclear program under international oversight, it cannot justify current enrichment levels.
"Yes, they can have a civil nuclear capability that's properly monitored, that involves outsiders, but they cannot continue to enrich to 60%... Why do they need 60% enrichment if not for a nuclear weapon?"
Despite the military action and growing tensions, Lammy underscored that diplomacy remains the only sustainable path forward.
"Ultimately, the only solution to dealing with the Iranian nuclear program was through diplomacy," he said. "Because the expertise still exists in the country, it's likely that some of the material still exists in the country."
