US President Donald Trump seemingly stepped back from declaring a national emergency to get the funds for his US-Mexico border wall, an "easy" option which he previously threatened to use, on Friday.

Speaking from the White House Cabinet Room alongside regional border security officials, Trump said "I'd rather not do it because this is something that Congress should easily do. This is something that the Democrats should do and I don't want to give an easy way out."

The president is reportedly facing opposition from senior figures within the Republican Party, who believe a national emergency could set an unjustified legal precedent.

Negotiations with the opposition collapsed on Friday, extending a federal stalemate on Capitol Hill.

Around 800,000 federal employees missed their first paycheck as the government shutdown marched on into its 21st day, becoming the joint longest in history.

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