Donald Trump wants Iran to strike a deal and to open the strategic Strait of Hormuz whose closure has led to a spike in oil prices.

The niece and grand-niece of Qasem Soleimani are in the custody of US Immigration and Customs Enforcement, officials said.

Under the law, travel approvals must generally be granted and it remains unclear how the rule would be enforced if breached.

The stakes could rise further if the weapons system officer of the downed F15 Eagle plane is captured by Iran.