US President Donald Trump said there was an "all-day negotiation" on Tuesday with Iran, characterising the talks positively while also threatening to hit Iran "really hard" if a deal with Tehran was not reached.

Details And Quotes:

• "They had an all-day negotiation," Trump told Fox News' "@ Night" show.

• "We are having very good discussions," he added.

• Qatar said on Tuesday mediators were making progress in efforts to end the Iran war, although Tehran has denied Trump's assertion that talks were under way.

• The Strait of Hormuz "is going to be open very soon," Trump said, warning that if that did not happen, Iran would be hit hard.

• "If they back out again, they are going to get hit really hard," Trump said.

• Iran blocked the Strait of Hormuz, a main route for energy supplies from the Middle East, after the start of the war.

• The Iran war began on Feb ‌28 when the US and Israel attacked Iran and ⁠Tehran responded with its own strikes on Israel and Gulf states that host US bases.

• US-Israeli strikes on Iran and Israeli attacks on Lebanon have since killed thousands and displaced millions.

• Trump's rhetoric during the war has been condemned by rights experts when he has threatened to target Iranian civilian infrastructure and when he threatened to destroy their civilisation in April.

• Iran has warned that if the US carried out such threats, Iranian forces would target regional energy and economic facilities.

• The 1949 Geneva Conventions on ⁠humanitarian conduct in war prohibit attacks on sites considered essential for civilians.

• Such attacks could amount to war crimes, international law experts in the ⁠US said in April, after Trump's previous threats.