Washington DC, Feb. 16 -- : A defiant US President Donald Trump on Friday (local time) declared a national emergency to bypass Congress and fulfill his long-pending demand of building a wall along the border with Mexico.

Defending his move, Trump asserted that he had "no choice" but to use his emergency powers to stop illegal immigrants spreading crime and drugs.

"I am going to be signing a national emergency. It's a great thing to do because we have an invasion of drugs, invasion of gangs, invasion of people," The Hill quoted Trump as saying at a press conference in Rose Garden.

Acknowledging that his move could be challenged legally, Trump remarked that his decision would eventually prevail. He said that he could wait for a "long time"...