American immigration laws are obsolete weak and pathetic: Trump

US President Donald Trump, who has been pushing for a merit-based immigration system, today said that the country's existing immigration laws are obsolete, weak and pathetic.

The United States, he said, has been facing massive flow of illegal immigrants.

"To protect Americans from these menaces, I have called on Congress to close deadly immigration loopholes that are exploited by terrorists, traffickers and criminals," he said.

"Just look at our southern border and our weak and obsolete immigration laws. They are obsolete and they are weak and they are pathetic. And there's no country in the world that has laws like we do. They've got to change and they've got to change now for the safety of our country," Trump told a joint Rose Garden news conference with the visiting Nigerian President Muhammadu Buhari.

Responding to reporters' questions, Trump ruled out any apology by him on his past remarks on illegal immigrants.

"And there's no reason to apologise. Our immigration laws in this country are a total disaster. They're laughed at all over the world. They're laughed at for their stupidity. And we have to have strong immigration laws," he said.

"If I apologize, it wouldn't make 10 cents worth of difference to them. There's nothing to apologise for. We have to have strong immigration laws to protect our country," he said.

Trump said the US is closely watching the developments on the southern border wherein more than 100 people are waiting to cross the border illegally. The caravan was initially of thousand people.

"We are a nation of laws. We have to have borders. We don't have borders, we don't have a country. I've been watching for weeks as the caravan came up. The Mexican laws are very tough on immigration, extremely tough," he said.

Noting that it started out with way over a thousand people, he said, it's down to about a hundred going all through Mexico.

"Now we're working on the border with the worst laws any country -- no matter where you go, all over the world, they can't even believe it. And we're doing the best we can with it. But we have to have changes in Congress, and we have to have it quickly," he said.

Trump said that the country now needs a wall.

"You see that right now, where they are, even though it's not a particularly good wall, and even though a small percentage can climb to the top, they have to be in extremely good shape. But a small percentage can climb that particular wall. We have a wall that's much more difficult," he said.

"But if you didn't have that, you'd have thousands of people just pouring into our country. You got to have a wall. We need border security," he said as he pushed for changing the current catch and release law.

"Catch and release is ridiculous. If they touch our property, if they touch our country, essentially, you catch them and you release them into our country. That's not acceptable to anybody. So we need a change in the law," Trump said in response to a question.