UK warns of “dramatic sanctions” against Iran if uncertainty on nuclear remains

The UK has issued a stern warning to Iran, with Foreign Secretary David Lammy telling parliament that Tehran must end the uncertainty surrounding its nuclear program or face “dramatic sanctions” in the coming weeks.

Speaking before the Foreign Affairs Select Committee on July 8, Lammy said that unless Iran allows the return of UN nuclear inspectors and recommits to diplomatic engagement, the UK, alongside France and Germany, could trigger the “snapback” mechanism under the 2015 Iran nuclear deal — reimposing broad UN sanctions, Caliber.Az reports, citing The Guardian.

“Iran faces even more pressure in the coming weeks because the E3 can snap back on our sanctions, and it’s not just our sanctions, it’s actually a UN mechanism that would impose dramatic sanctions on Iran across nearly every single front in its economy,” Lammy said.

“So they have a choice to make. It’s a choice for them to make. I’m very clear about the choice they should make, but I’m also clear that the UK has a decision to make that could lead to far greater pain for the Iranian regime unless they get serious about the international desire to see them step back from their nuclear ambitions," he added. 

The UK’s position has been echoed by France, which is closely coordinating with London to push Iran toward renewed talks with the United States. The three European signatories of the 2015 deal — known as the E3 — retain the right to restore UN sanctions without Security Council approval, provided they act before the October deadline set in the agreement.

Tensions remain high as Iran maintains a fragile ceasefire with both Israel and the United States. However, with no clear breakthrough in sight, officials fear the situation could escalate into renewed conflict if diplomacy fails.

Lammy warned that Tehran’s recent suspension of cooperation with UN nuclear inspectors “will only lead to greater uncertainty about their nuclear intentions,” describing it as a “stark violation” of the nuclear non-proliferation treaty (NPT). The reinstated sanctions would include cargo inspections on Iranian shipments, an arms embargo, and restrictions on missile-related technologies.

While withholding judgment on Israel’s recent strike on Iran’s nuclear facilities, Lammy acknowledged that Iran’s technical capacity to develop a nuclear weapon remains intact despite physical damage to its centrifuges and uranium stockpiles.

“Iran would retain its knowledge of how to build a nuclear weapon – making it necessary for the west to reach some diplomatic agreement,” he said.

He also addressed the potential for further Israeli military action, saying, “Iran has lost its air defences and I suspect the Israelis, monitoring Iran very closely, are free to act again, if they think they can further degrade Iran’s nuclear capability.”

Lammy added that neither Russia nor China had shown signs of coming to Iran’s defence in the wake of recent developments.

Iran has not ruled out re-engaging with the US, though growing domestic pressure within the country makes renewed negotiations politically sensitive. Talks expected to take place in Oslo this week failed to materialize.

Meanwhile, the US continues to insist on strict conditions for any diplomatic progress. Over the weekend, US special envoy Steve Witkoff reaffirmed that Washington would only return to negotiations if Iran halts its uranium enrichment — a condition Iran has long considered non-negotiable.

By Sabina Mammadli