Lawmakers are seeking the US president to require congressional approval before further military action against Iran

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Congress is about to launch a war powers debate over president Donald Trump’s authority to bomb Iran under largely unusual circumstances - he has already done it, and the country is essentially already at war, reports AP.

The moment is a defining one for Congress, which alone has the authority under the US Constitution to declare war, and for the Republican president , who has consistently seized power during his second term with an apparent limitless view of his own executive reach.