In a 59-41 vote, in which 12 Republicans defied the president, the Senate passed a measure to rescind the national emergency declared by Mr Trump last month in a move widely seen as a means to circumnavigate a Congress that had rejected his demand for more than $8bn in funding for a border wall.

The House of Representatives has already passed the bill, and it now goes to the White House, where Mr Trump has vowed for the first time to use his veto powers. Indeed, Mr Trump immediately reacted to the news with a single-word tweet that said: “VETO”.

Whether there are enough numbers to overturn Mr Trump’s expected move – a two-thirds vote of both chambers of Congress is needed to override a presidential veto – is unclear.

What it certainly does is place Mr Trump’s demand for a border wall and Democrats’ refusal to fund one front-and-centre as the 2020 presidential election campaign starts to gather pace.

Trump prototypes for Mexico border wall demolished in California Show all 20 1 /20 Trump prototypes for Mexico border wall demolished in California Trump prototypes for Mexico border wall demolished in California The prototypes for President Trump’s border wall are being demolished. AP Trump prototypes for Mexico border wall demolished in California The US Customs and Border protection had built the eight 30-foot tall steel and concrete models near San Diego on the US-Mexico border. Reuters Trump prototypes for Mexico border wall demolished in California A 2018 report from the Government Accountability Office found that the construction challenges presented by the four concrete models would be “extensive” and those presented by two of the other models would be “substantial”. Reuters Trump prototypes for Mexico border wall demolished in California It was intended that Mr Trump would choose his favourite of the designs after testing had been completed. AFP/Getty Trump prototypes for Mexico border wall demolished in California The President is yet to comment. AFP/Getty Trump prototypes for Mexico border wall demolished in California Each prototype cost $300,000 to $500,000 to build and they are being knocked down in order to make way for the San Diego Secondary Wall project which will see up to 14 miles of barrier being built to support the existing steel border fence. AP Trump prototypes for Mexico border wall demolished in California The new barrier will not employ the design of any of the prototypes, instead being built of the favoured steel bollards which make up the current section of the wall at San Diego. Reuters Trump prototypes for Mexico border wall demolished in California The new secondary barrier being built near San Diego. Reuters Trump prototypes for Mexico border wall demolished in California The rubble of one of the demolished prototypes. Reuters Trump prototypes for Mexico border wall demolished in California A steel wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A wall prototype made from a mix of steel and concrete AFP/Getty Trump prototypes for Mexico border wall demolished in California A wall prototype made from a mix of steel and concrete AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A steel wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A digger approaches the prototype wall AFP/Getty Trump prototypes for Mexico border wall demolished in California Aerial view of the wall prototypes at the US-Mexico border after they were torn down AFP/Getty Trump prototypes for Mexico border wall demolished in California An aerial view showing Tijuana, Mexico on the left and the demolished wall prototypes on the right AFP/Getty

When Mr Trump announced the state of emergency in February, during a meandering 50-minute appearance in the Rose Garden of the White House, he claimed he was taking the measure on the grounds of national security.

“We’re talking about an invasion of our country with drugs, with human traffickers, with all types of criminals and gangs,” he said.

“I didn’t need to do this, but I’d rather do it much faster.”

Commentators pointed out that the vast majority of drugs entered the country thought its legal crossing points. Rather, critics said, the president was seizing on the issue to try and rally his base as he prepared for a tough re-election battle.

Alec Baldwin mocks President Donald Trump’s emergency declaration

Reuters said those Republicans who defected on Tuesday by supporting the measure to end the emergency declaration, were worried about executive creep – namely, that presidents, including future Democratic ones, could seize the powers traditionally held by Congress to fund the government and use the tactic to pass their own pet programmes and schemes.

The Republican leader in the Senate, Mitch McConnell, claimed the president was “operating within existing law” and that if senators did not like the powers provided to the president under the National Emergencies Act, “then they should amend it”.

Senator Angus King, one of two Senate independents, said of the vote: “It’s an important legal statement. It tells the court this is explicitly not approved by Congress By voting this resolution Congress is reiterating we don’t approve of this expenditure.”

The vote marked the second congressional rebuke for the president in as many days.