White House says Iran hostilities 'terminated' as Trump seeks to dodge Congress showdown

On Friday US time, President Donald Trump by law is required to pull American forces out of the war with Iran unless Congress grants a last-minute authorisation of the conflict.

As with many things involving the unorthodox commander-in-chief, however, what should happen does not always correspond to what will.

And the White House has already said the deadline does not apply, given that US forces have not exchanged fire with Iran for weeks, effectively stopping the clock and granting Trump another 60-day conflict window if active hostilities resume - should Congress accept the rationale.

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But in this case, Trump for once is not acting without precedent.

In the US, congressional approval is theoretically necessary for any war the US embarks on, but multiple presidents have found loopholes there.

The War Powers Resolution of 1973 - intended to bolster that privilege of Congress - nonetheless handed Richard Nixon and every subsequent president a fairly major loophole.

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Whoever's in the Oval Office must, within 48 hours of committing US troops to hostile action, provide to Congress a report outlining the authority under which the decision was made, the justification for it, and an estimate of the length of US involvement.

And 60 days after that report is submitted, if Congress has not authorised the war, troops have to be recalled.

Trump's 60-day window ends on May 1 local time - which began when the clock hit midnight in Washington DC at 2pm AEST yesterday.

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Congress has not authorised the war, nor have they voted to grant a 30-day extension. Democratic efforts to limit Trump's ability to engage in the conflict have been repeatedly thwarted by Republicans.

What happens next?

Defence Secretary Pete Hegseth flagged the Trump administration's short-term approach during his appearance before Congress this week to answer questions on the Iran war.

Hegseth claimed "the 60-day clock pauses or stops in a ceasefire", referring to the situation currently in place.

Trump unilaterally extended the ceasefire just as it was set to expire, but official talks between Iran and the US have not resumed.

And the White House has claimed "the hostilities that began on February 28 have ended", according to Associated Press.

Democrat Senator Tim Kaine said he had "serious constitutional concerns" over that stance and that he did not believe the law supported that view.

But Trump isn't the first to take it.

Then-president Barack Obama did the same during US operations in Libya in 2011, claiming the 60-day clock had not ticked over because US forces weren't currently engaged with enemies.

Trump could also challenge the law in the courts on claims it's unconstitutional, as Nixon attempted to.

He could also, of course, simply ignore the legal mandate to withdraw troops and count on Republicans in Congress to block attempts to challenge him.

But given the war's deep unpopularity in the US (just 34 per cent of voters approve), Trump's shrunken approval ratings, and the looming midterms, nervous Republicans may be less inclined to bow to the president's whims.

GOP Senator Susan Collins said the deadline was not a "suggestion".

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