President Donald Trump, pictured in the Oval Office of the White House on February 24, saidn the wall between Mexico and the US will be built ‘soon’ way ahead of schedule’. Picture: Pablo Martinez Monsivais

Mr Trump told the nation’s largest gathering of conservative activists, the Conservative Political Action Congress, in Washington, that he vowed to always put American citizens first and build a “great, great border wall”.

“We’re building the wall,” he said.

“In fact it’s going to start very soon. Way ahead of schedule. It’s way, way, way ahead of schedule.”

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President Donald Trump said the proposed border wall would be built as he promised. Picture: Pablo Martinez MonsivaisSource:AP

US Customs and Border Protection then released it plans to start awarding contracts by mid-April for the proposed border wall.

The agency said on a website for federal contactors that a request for bids would be published on or around March 6. Companies would have to submit “concept papers” to design and build prototypes by March 10. CBP will narrow the field by March 20 and require that finalists renew their offers by March 24, with a price attached.

The timetable shows that Trump is aggressively pursuing plans to build what he calls “a great wall” on the 2,000-mile border with Mexico.

His comments come a day after Secretary of State Rex Tillerson and Homeland Security Secretary John Kelly met their Mexican counterparts in Mexico City.

The wall could cost up to $US21.5 billion, according to Reuters, citing a Department of Homeland Security internal report — much higher than Mr Trump’s estimated price tag of $12 billion.

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Immigrant residents and activists demonstrate outside of the Elizabeth Detention Centre, New Jersey, which is holding people awaiting deportation. Picture: Spencer PlattSource:AFP

Mr Trump conceded that he had sent Mr Tillerson and Mr Kelly on a “tough trip” as he continued to talk tough about immigration.

“You see what’s happening at the border. All of a sudden for the first time, we’re getting gang members out. We’re getting drug lords out. We’re getting really bad dudes out of this country, and at a rate that nobody’s ever seen before,” he said.

“They’re the bad ones, and it’s a military operation.”

Mr Kelly later stated there would be “no use of military forces”.

“We are not going out and doing mass deportations. We have laws that I must follow so we will be looking primarily at criminal offenders first,” he said, “so there will be no mass roundups.”

Trump told the Conservative Political Action Congress that his role was to serve the United States and not the rest of the world.

“This is the United States of America I’m representing. I’m not representing the globe. I’m representing your country.” he said.

Mr Trump also promised to focus on “getting bad people out of this country”.