Donald Trump has revealed what his Mexican border wall will look like - calling its design "beautiful".

The United States President unveiled a steel, spiked design for the controversial wall posting on Twitter last night.

His tweet, calling the plans "effective" and "beautiful" came hours after he effectively shut down US government in retaliation for congress refusing to budget for the infamous wall.

President Trump wrote: "A design of our Steel Slat Barrier which is totally effective while at the same time beautiful!"

White House negotiators left Washington on Friday having failed to agree a spending deal, with Trump demanding billions of dollars for the fence, The Sun reports.

The US President unveiled designs for the 'effective' and 'beautiful' wall (
Image:
Real Donald Trump/Twitter)

He promised a "very long" shutdown from midnight if the Senate did not agree the £4.5bn ($5.7bn) he is demanding.

"I hope we don't but we are totally prepared for a very long shutdown," he said during a White House event.

In the likelihood that the Democrats do not agree the funding - Trump says he will force the partial shut down.

This will see all national parks and forests closed.

However federal programmes will still function, as will the military, border patrol, coast guard, federal judiciary, air traffic control and airport security.

The US Postal Service will not be affected by the government shutdown as it's an independent agency.

Federal workers who are deemed "essential" will also remain on the job, but will not receive a pay cheque directly before the Christmas holiday.

Trump will 'force partial shut down' if the Democrats do not agree to fund the wall (
Image:
SHAWN THEW/EPA-EFE/REX/Shutterstock)

Nine federal departments will be shut down along with the government: Department of the Treasury, Agriculture, Homeland Security Department, Department of the Interior, Department of State, Housing and Urban Development, Transportation, Commerce and the Department of Justice.

Trump tried to bait the Democrats into supporting him, tweeting: "Cancelled my trip on Air Force One to Florida while we wait to see if the Democrats will help us to protect America’s Southern Border."

He also posted a video saying: "We don't want people coming in who are not supposed to be here."

Trump said "a wall, a slat fence" or a "great barrier" was needed, and urged the Democrats to be "bipartisan and get this done."

The President also posted a crude drawing of the wall, featuring pointed spear-like tops and a security van patrolling the base.