Washington, March 15 -- In a stunning rebuke to Donald Trump, a dozen Republican senators broke party ranks and sided with Democrats to terminate the US President's declaration of a national emergency on America's border with Mexico.

In a 59-41 vote, 12 Republicans joined every Senate Democrat on Thursday in a rare move to block the president's effort to divert billions in funding to build his long-promised border wall without congressional approval.

The Democratic-controlled House of Representatives last month backed the measure.

The Republicans joined Democrats in voting down the emergency, arguing that the president had exceeded his powers in trying to build a border wall over Congress' objections, the New York Times reported.