The first thing I will do is declare a national emergency on our southern border, said the new US President Donald Trump.
"All illegal entry will be immediately stopped. We will begin the process of returning millions" of illegal immigrants, he said in his inaugural speech.
"I will send troops to our southern border to repel a catastrophic invasion of our country," Trump also said, whose speech was broadcast live by the Associated Press and major American television networks.
Trump promised to declare drug cartels in Latin America foreign terrorist organizations and to take strict measures against the actions of gangster groups on US territory.