US President Donald Trump said on Wednesday that the memorandum of ​understanding (MOU) signed with Iran to end the conflict ‌is "over," adding he didn't want to engage with Tehran.

The interim ceasefire agreement signed between Washington and Tehran, mediated by Pakistan, was intended to provide a 60-day window ​for negotiations on a permanent agreement, but indirect talks in Qatar ended with no sign of ​headway, and the US military unleashed a new wave of strikes ​against Iran on Tuesday.

"To me, I think it's over. I don't want to deal with them," Trump said ahead of a ​NATO summit in the Turkish capital, Ankara.

"They're scum. They're ​sick people. They're led by sick people," he said alongside NATO ‌Secretary General Mark Rutte. "As far as I'm concerned, it's just a waste of time dealing with them."

The US on Tuesday also revoked a license allowing Iran to sell ​oil after three ​tankers were hit by projectiles in the Strait of Hormuz.

Under the interim US-Iran MOU, the US Treasury issued a license to allow the sale of crude oil, petrochemicals, and petroleum products of Iranian origin through August 21. In revoking that license on Tuesday, the US gave Iran until July 17 to wind down any transactions.