US President Donald Trump has said the US-Iran ceasefire is over following renewed military strikes between the two countries, in comments reported on July 8.

The remarks signal the collapse of a fragile accord reached last month to halt the Middle East war, raising the prospect of a prolonged confrontation that has already disrupted shipping through the Strait of Hormuz and pushed oil prices higher.

"As far as I'm concerned, it's over," Trump told reporters at the Nato summit in Ankara, referring to the memorandum reached with Tehran.

The comments came after the US and Iran traded military strikes, with Washington saying it was responding to attacks on ships by Iran in the Strait of Hormuz.

US Central Command announced what it called powerful strikes against Iran on the evening of July 7 in Washington, hours after the Treasury revoked a general licence allowing sales of Iranian oil. Iran's Islamic Revolution Guards Corps said its forces had responded with missile and drone strikes early on July 8, targeting 85 US military sites.

Trump said the US had wasted a great deal of time on Iran and would not allow it to obtain a nuclear weapon, according to Jamaran. He said Washington wanted Iran to scale back its nuclear weapons programme, describing the issue as important for Israel and Europe.

"The memorandum on ending the war with Iran is over for me," Trump said, adding that he did not want to deal with Iranians, Jamaran reported. He said the decision on whether to continue negotiations with Iran rested with US negotiators Steve Witkoff and Jared Kushner.

Trump said he would allow the senior negotiators to continue talks if they wished, but that he considered this unlikely, according to the outlet. He also said he was not satisfied with Nato's position on Iran, and that Turkey would obtain F-35 fighter jets.