A fragile ceasefire in the Iran war came under pressure on Thursday as disagreements over Lebanon, the Strait of Hormuz and other key issues cast doubt on whether the truce will hold.
Just hours after the ceasefire was announced, confusion emerged over whether it covered fighting between Israel and Hezbollah. Soon after, Israel launched heavy airstrikes on Beirut, marking the deadliest day in Lebanon since the conflict began on Feb. 28.
Iran and the United States, both claiming success after the truce, appeared to be increasing pressure on each other. Iranian semiofficial media suggested that forces may have planted sea mines in the Strait of Hormuz, a vital global oil route, highlighting Tehran’s strategic leverage. Meanwhile, President Donald Trump warned that US forces would carry out stronger attacks if Iran fails to honour the deal.
However, major questions remain unresolved. These include whether Lebanon is part of the ceasefire, the future of Iran’s enriched uranium stockpile, when normal shipping will resume through the strait, and limits on Iran’s missile capabilities.
Iran’s nuclear chief Mohammad Eslami said protecting the country’s right to enrich uranium is essential for any agreement with Washington. Speaking in Tehran, he criticised the US for not recognising enrichment as part of Iran’s proposed plan for a lasting ceasefire.
Talks between the US and Iran are expected to take place in Pakistan this weekend.
Violence in Lebanon has further threatened the truce. At least 182 people were killed on Wednesday as Israel intensified strikes on Hezbollah positions in Beirut. Rescue teams continued searching through rubble for survivors.
Israel said it killed Ali Yusuf Harshi, an aide to Hezbollah leader Naim Kassem, though Hezbollah has not commented.
Iranian Foreign Minister Abbas Araghchi insisted that halting the war in Lebanon was part of the ceasefire, but Israeli Prime Minister Benjamin Netanyahu and Trump rejected that claim.
A New York-based think tank warned the agreement is close to collapse, saying Israel’s large-scale strikes could be seen as escalating tensions, regardless of whether Lebanon is formally included.
Lebanon’s state news agency reported that an Israeli strike killed at least seven people in the south overnight, though Israel has not confirmed it.
Uncertainty over the Strait of Hormuz continues to push global oil prices higher. Iranian media published a map indicating a “danger zone” in the waterway, suggesting the presence of sea mines during the conflict.
Shipping traffic through the strait has dropped sharply, with only a few vessels passing since the war began due to security concerns. Although prices briefly fell after the ceasefire announcement, they rose again as doubts grew. Brent crude stood at around $98 on Thursday, up about 35% since the conflict started.
Iran has said it will allow ships to pass under international law once US military actions stop and Israel halts attacks in Lebanon.
Trump said US forces would remain deployed near Iran until a “real agreement” is fully implemented, warning of stronger military action if commitments are not met.
The White House said Vice President JD Vance will lead the US delegation in upcoming talks in Islamabad starting Saturday.
Key sticking points include Iran’s plan to potentially charge ships using the strait, which would challenge its status as an international waterway, and the future of Iran’s nuclear and missile programmes.
While the US wants Iran to abandon any ability to develop nuclear weapons and remove its stockpile of highly enriched uranium, Tehran maintains its programme is for peaceful purposes.
Trump said the US may work with Iran to remove the uranium, though Tehran has not confirmed this. In its own version of the agreement, Iran indicated it would continue uranium enrichment.