President Donald Trump on Sunday issued a sharp warning to Tehran, demanding that Iran immediately halt the activities of its proxies in Lebanon or face severe consequences.

He declared that the United States would strike Iran "very hard again," escalating tensions even as negotiators from both sides continue delicate peace talks in Switzerland.

The statement was delivered through his social media platform, Truth Social, and marked one of the most aggressive interventions by Washington since the alpine diplomatic track began.

Trump’s post emphasised that Iran’s “highly paid proxies” in Lebanon must stop causing trouble, threatening that if they did not, the US would retaliate even more forcefully than in the previous week’s strikes.

This rhetoric arrived at a critical juncture, coinciding with technical-level negotiations under the framework of a recently signed Memorandum of Understanding. The MoU outlines a structured agenda to address disputes over regional security, maritime access through the Strait of Hormuz, Iran’s nuclear programme, and ceasefires across multiple fronts. It establishes a strict sixty-day window dedicated to reducing friction and working towards a durable settlement.

US Vice President JD Vance, speaking from Switzerland, highlighted progress in stabilising the Lebanese border despite the volatile situation on the ground. He noted that the ceasefire in Lebanon had shown signs of holding, though he acknowledged the inherent difficulties of managing truces among hostile factions.

Vance described such ceasefires as “always a little bit messy,” but maintained optimism about the overall trajectory of the talks. He stressed that President Trump remained committed to achieving a comprehensive cessation of hostilities across West Asia, with the Lebanese front seen as a crucial prerequisite for broader regional peace.

Vance underscored that the current deliberations offered a historic opportunity to reshape long-strained relations with Tehran, provided Iran abandoned destabilising activities. He affirmed Washington’s aspiration to “turn over a new leaf” with Iran if the leadership demonstrated genuine commitment to peace.

However, the diplomatic momentum has been hindered by Tehran’s refusal to advance into the next phase of dialogue without certain preconditions being met. Iranian negotiators have insisted that Israeli military operations in Lebanon must cease entirely before substantive talks on sensitive issues, including Iran’s nuclear programme, can proceed.

Iran has also demanded immediate economic relief and financial dividends promised under earlier agreements with Washington and its allies. Tehran has accused the US of failing to exert sufficient pressure to halt Israeli cross-border operations, which have seen regular exchanges of fire between Israeli forces and Hezbollah since March.

This impasse has been compounded by Iran’s decision to reinstate its maritime blockade of the Strait of Hormuz, a vital global trade artery handling nearly a fifth of the world’s energy supplies. The move directly contravenes the provisions of the MoU, which called for reopening the strait and de-escalating tensions in the waterway.

Iran’s strategy remains firmly conditional, linking its cooperation to concrete security guarantees on the Lebanese border and the swift fulfilment of Washington’s financial commitments. This multi-layered leverage approach has added further strain to the already fragile dialogue, leaving the peace process delicately balanced between progress and collapse.

ANI