The US president has until Friday to pledge continued support for a landmark international deal with Iran over its nuclear programme.
Donald Trump has described the agreement, brokered under his predecessor Barack Obama, as an "embarrassment" to the US.
He's threatened to pull out of the deal altogether unless changes are made.
Trump’s refusing to recertify the deal unless Congress amends it.
But as Congress didn’t draw up the deal - it’s not down to them to change it.
Any alterations it makes with the president would be in breach of the international agreement.
Al Jazeera's Neave Barker reports.
