US leader’s remarks come hours after Iranian president claims some mediation efforts are under way

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Donald Trump has demanded Iran’s “unconditional surrender”, only hours after the country’s president, Masoud Pezeshkian, claimed some mediation efforts to end the war were under way.

The US president’s remarks on Friday hit European stock markets, which were already suffering after a warning from Qatar that a prolonged shutdown of gas production could drive oil to more than $150 a barrel. It was $90 on Friday.

Choice of anti-western candidate would give signal that senior figures will not seek accommodation with US

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Mojtaba Khamenei, the second son of the assassinated Ali Khamenei, is being heavily tipped to succeed his father as supreme leader of Iran, which would pitch a hardliner into the task of steering the Islamic republic through the most turbulent period in its 48-year history and offer a powerful signal that, for now, it has no intention of changing course.

No official confirmation has been given and the announcement may be delayed until after the funeral of Ali Khamenei, which was on Wednesday postponed.

Strikes on Iranian leadership are putting Tehran under unprecedented military and diplomatic pressure

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Iran endured a day of unprecedented military and diplomatic pressure on Tuesday as US airstrikes pushed the death toll in the country close to 800 and the offices of the assembly of experts – the body due to select a replacement for the assassinated supreme leader, Ali Khamenei – were bombed.

It would be an extraordinary security lapse if it emerges that many of the 88 elderly clerics on the assembly had been in the building in Qom voting at the time. “There was another hit today on the new leadership, and it looks like that was pretty substantial,” Trump said at a White House event, although it was unclear what specifically he was talking about.