Donald Trump slammed for 'disgusting and disgraceful' question he asked workers outside the White House

President Donald Trump couldn't even get through the unveiling of two new flagpoles without slipping in a flagrant reference to his immigration policies yesterday (18 June).

The 79-year-old stood on the South Lawn of the White House, admiring the new installations alongside the workers who had erected them, before he asked a bizarre question that has sparked uproar online.

He held a press conference at the presidential residence in Washington on Wednesday to commemorate the arrival of two 88-foot-tall flagpoles, which he described as 'a gift' from him.

They now sit on the North and South Lawns, much to the delight of Trump, who dubbed them the 'most magnificent poles made'.

In a social media post, he wrote: "It is my Great Honour to announce that I will be putting up two beautiful Flag Poles on both sides of the White House.

Donald Trump was celebrating the installation of two 'magnificent' flag poles at the White House yesterday (BRENDAN SMIALOWSKI/AFP via Getty Images)

"It is a GIFT from me of something which was always missing from this magnificent place. These are the most magnificent poles made - They are tall, tapered, rust proof, rope inside the pole, and of the highest quality.

"Hopefully, they will proudly stand at both sides of the White House for many years to come!"

But he got straight back to business after all the flagpole formalities were out of the way and he began chatting to reporters.

One journalist asked the commander-in-chief about his amped up efforts to deport so-called 'illegal aliens' from the US in recent days, to which Trump replied: "We're taking them out by the thousands.

"Murderers, drug dealers, people that are mentally insane, from insane asylums."

He then interrupted his own train of thought to turn and weigh up the hard hat-wearing workmen standing behind him, before shockingly deciding to quiz them about their immigration status.

Take a look at this:

Mumbling incoherently as he spun around to face the tradesmen, Trump said: "Do we have anybody here who's a member of... no, I don't think so.

"You've known these people for a long time? Any illegal immigrants?"

At this point, a few of the workmen flanking him shook their heads to answer his question, before Trump continued: "If they were, they'd find out. They'll be checking you... You won't believe.

"Your whole life will be destroyed because of this press conference, watch - they'll destroy these people.

"I didn't want to tell them that before they stood up... They'll end up going, 'He's so and so, this one is from you know where'.

"Don't worry, I think you're going to be okay. I'll be right behind you. Far behind you," he added while laughing. "No, I'll be right behind you."

The president has been slammed for quizzing the workmen about their immigration status (BRENDAN SMIALOWSKI/AFP via Getty Images)

Although the workmen appeared to take the outlandish comment on the chin, people online couldn't believe that the president had posed such a question to the workers on live TV.

One social media user said: "This isn't 'lmao'. This is disgusting and disgraceful. Wtf."

Another fumed: "What an absolute a**hole."

A third commented: "Wow! Threatening workers on TV, way to go! Smh!"

While a fourth chimed in saying: "He's embarrassing and has made the US the laughing stock of the world."

It comes after Trump launched into a tirade about the possibility of launching military strikes on Iran in front of a row of bemused Juventus players - and the footie stars' faces were quite the picture.