A US-Iran ceasefire that began in early April has "terminated" hostilities between the two sides for the purposes ​of an approaching congressional war powers deadline, a senior official of President Donald Trump's ‌administration said on Thursday.

Trump faced a deadline on Friday to end the Iran war or make the case to Congress for extending it, but the date was most likely to pass without altering the course of ​the war.

"For War Powers Resolution purposes, the hostilities that began on Saturday, 28 February, have terminated," said the official, describing the administration's thinking.

There has been no ⁠exchange of fire between the US armed forces and Iran since a fragile ceasefire ​began more than three weeks ago, the official added.