New York: Donald Trump has issued the first veto of his presidency, rejecting a resolution that would have stopped him from funding a wall on the US-Mexico border without the approval of Congress.
On Thursday, local time, 12 Republican senators sided with Democrats to reject Trump's declaration of a national emergency on the southern border.
This came after the Democrat-controlled House of Representatives passed the same resolution last month.
Speaking at the Oval Office on Friday, Trump said the congressional action was "dangerous" and "reckless".
"I am vetoing this resolution," Trump said. "Congress has the freedom to pass this resolution and I have the duty to veto it."
Trump said that the nation's "immigration system is stretched beyond the breaking point" and that only a physical barrier could stop drugs and dangerous people entering the country.
Democrats have accused Trump of manufacturing a border crisis in order to fulfil a campaign promise to build a wall.
For the veto signing, the President was accompanied by law enforcement officials and the families of people killed by illegal immigrants.
Congress could override Trump's veto with two-thirds support in the House and Senate but this looks extremely unlikely to happen.
The national emergency declaration is also being tested in the judicial system and may well make its way to the Supreme Court.
Many of the Republican defectors said they supported a border wall but that they opposed the use of a national emergency declaration to fund it.
"This is a vote for the constitution and for the balance of powers that is at its core," Republican Senator Mitt Romney said on Thursday.
"For the executive branch to override a law passed by Congress would make it the ultimate power rather than a balancing power."
Previous presidents Barack Obama and George W Bush issued twelve vetoes each during their two-term presidencies while Bill Clinton vetoed legislation 37 times.