Trump:Iran hasn't lived up to nuclear deal

US President Donald Trump says Iran has not lived up to the spirit of the nuclear deal agreed with world powers and suggested he would reveal his decision on whether to certify the agreement soon.

"We must not allow Iran ... to obtain nuclear weapons," Trump said during a meeting with military leaders at the White House on Thursday.

"The Iranian regime supports terrorism and exports violence, bloodshed and chaos across the Middle East. That is why we must put an end to Iran's continued aggression and nuclear ambitions. They have not lived up to the spirit of their agreement," he said.

Asked about his decision on whether to certify or decertify the landmark nuclear deal, Trump said: "You'll be hearing about Iran very shortly."