President Donald Trump blasted mass migration and climate-change agreements during a speech at the United Nations General Assembly aimed at flexing American strength abroad.

“I've come here today to offer the hand of American leadership and friendship to any nation in this assembly that is willing to join us in forging a safer, more prosperous world,” Trump said Sept. 23. “But to get there, we must reject the failed approaches of the past and work together to confront some of the greatest threats in history.”

White House press secretary Karoline Leavitt had billed the speech as a major foreign-policy address where Trump would describe “the return of American strength” and deliver “blunt” and “tough talk” about the “failures of globalism."

Trump urges end to wars in Gaza, Ukraine

Trump endorsed peacekeeping initiatives to end wars in Gaza and Ukraine and criticized the United Nations for not doing more. He called for a ceasefire in Gaza and for Hamas to release its remaining few dozen hostages, both dead and alive.

“We have to stop the war in Gaza immediately,” Trump said. “We have to stop it.”

But Trump criticized the United Nations for basically sitting on the sidelines writing strongly worded letters rather than resolving conflicts around the world.

“It has tremendous potential, but it’s not even coming close to living up to that potential for the most part,” Trump said. “All they seem to do is write a really strongly worded letter and then never follow that letter up. It's empty words, and empty words don't solve war.”

Trump urges Europe to close borders to immigration

On immigration, Trump urged European countries to close their borders like he had for the U.S. rather than allow caravans of thousands of migrants to enter.

“We have successfully repelled a colossal invasion,” Trump said. “Our message is very simple. If you come illegally into the United States, you're going to jail, or you're going back to where you came from, or perhaps even further than that.”

He cited statistics from the Council of Europe that nearly half the inmates in German prisons – and more than half in Austria and Greece – were foreign nationals or migrants.

“It's time to end the failed experiment of open borders. You have to end it now,” Trump said. “Your countries are going to hell. In America, we've taken bold action to swiftly shut down uncontrolled migration.”

Trump blasts climate-change agreements as a 'hoax' and 'con-job'

Trump also blasted climate-change agreements as a “hoax” and a “con-job” because even as Europe reduced its greenhouse-gas emissions, China increased theirs. He criticized wind and solar energy projects as too costly.

Trump said the U.S. would continue producing oil, natural gas and coal – and supply energy to any country willing to pay.

“I'll be very badly criticized for saying it, but I'm here to tell the truth,” Trump said. “I don't care.”

Trump promoted U.S. leadership in the world. He said the country was a “laughingstock all over the world” during his predecessor’s administration, but that at the North Atlantic Treaty Organization in June members agreed to boost their defense spending to 5% of their economies.

“America is respected again, like it has never been respected before,” Trump said.

Trump's speech got off to a shaky start with a non-working teleprompter.

“I don’t mind making the speech without a teleprompter because the teleprompter is not working,” Trump said to laughter. “I can only say that whoever is operating this teleprompter is in big trouble.”

But about 10 minutes into the speech, Trump said the teleprompter had started working. But he said he might prefer to continue reading it the old-fashioned way, from paper in a binder on the podium in front of him.

“I feel very happy to be up here with you nevertheless,” Trump said. “That way you speak more from the heart.”

(This story has been updated with more information and photos.)

This article originally appeared on USA TODAY: Trump blasts open borders, endorses fossil fuels in UN speech

Reporting by Bart Jansen, USA TODAY / USA TODAY

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