President Donald Trump has suggested talks aimed at ending the war in Iran could resume this week, after negotiations collapsed at the weekend, prompting the US to blockade Iranian ports. 'You should stay there [Islamabad], really, because something could be happening over the next two days, and we're more inclined to go there,' Trump was quoted as saying in an interview with the New York Post.

His remarks came as the American military said no ships had passed through the US-enforced blockade of Iranian ports and coastal areas in the first 24 hours of the operation. The stand-off has raised doubts over the prospects for a two-week ceasefire that is due to expire next week.

The Iranian side has not yet responded to Trump's remarks, but United Nations Secretary General António Guterres said it was 'highly probable' that talks would restart. Gulf, Pakistani and Iranian officials also stated that negotiating teams from Washington and Tehran could return to Pakistan later this week, with no date yet agreed, according to Reuters news agency.

Hopes that diplomacy might continue helped soothe oil markets, pushing benchmark prices below $100 on Tuesday. Iran has effectively shut the Strait of Hormuz, a crucial global waterway for oil and gas transport, since it came under attack from US and Israeli air strikes on 28 February.

More than a dozen US warships and some 10,000 US military personnel are now enforcing the blockade against vessels of any country entering or leaving Iranian ports, starving Iran of a vital economic lifeline. It is aimed at putting pressure on Tehran by targeting two of the country's major money sources: oil revenue and the significant tolls Iran demanded from ships for passage through the critical waterway.

US Central Command (Centcom), which has responsibility for US military activity in the Middle East and parts of Central Asia, reported that six merchant vessels had complied with directions from American forces to turn around and return to Iranian ports in the first 24 hours of the blockade. Ship-tracking data analysed by BBC Verify showed that at least four Iran-linked shipping vessels had crossed the Strait of Hormuz despite the blockade.

Initial high-level negotiations that took place in the Pakistani capital of Islamabad over the weekend failed to produce any deal, with the US claiming that Iran had not agreed to its terms. The US had proposed a 20-year suspension of all uranium enrichment by Iran. But Tehran suggested a halt of five years instead. Vice-President JD Vance, who led the US negotiations, expressed belief that Iran wanted a deal, while China condemned the blockade as 'dangerous and irresponsible'.