US President Donald Trump warned Russia on Tuesday that he is prepared to impose strong economic measures if it does not work toward ending the war in Ukraine, and rejected a global move toward recognition of a Palestinian state in a combative speech to the U.N. General Assembly.

In a wide-ranging foreign policy speech that included scathing criticism of the United Nations and European nations, Trump made the case for lower levels of global migration and said world leaders should abandon efforts to fight climate change, which he called “the greatest con job” in the world.

Taken as a whole, the 56-minute speech was a rebuke to the world body and a return to form for Trump, who had routinely bashed the U.N. during his first term as president. Leaders gave him polite applause when he exited the chamber.

Trump’s warning to Russia was his latest attempt to pressure Russian President Vladimir Putin, who has resisted the US president’s entreaties to pull back from the biggest war in Europe since World War two.

Trump said he wants US allies to impose the same measures on Russia he is proposing to apply pressure to Putin.

The US president has warned about the possibility of sanctions on Russia several times but has yet to follow through. Lately he has demanded Europe stop all Russian oil purchases before he will take action.

“In the event that Russia is not ready to make a deal to end the war, then the United States is fully prepared to impose a very strong round of powerful tariffs, which would stop the bloodshed, I believe, very quickly,” he said.

But for the measures to be effective, he said, “European nations, all of you gathered here, would have to join us in adopting the exact same measures.”

He did not detail the measures, but he has been considering a package that includes sanctions against countries that do business with Russia, like India and China. The main buyers of Russian oil in Europe are Hungary, Slovakia and Turkey.

Trump planned a meeting later in the day with Ukrainian President Volodymyr Zelensky, who has been pressing for more US support to resist Russian advances.

On the Israel-Palestinian conflict, Trump gave a thumbs down to efforts by world leaders to embrace a Palestinian state, a move that faces fierce resistance from Israel.

“The rewards would be too great for Hamas terrorists, for their atrocities,” he said, repeating his call for the return of hostages taken by the Palestinian militant group.

Trump said the United States wants a ceasefire-for-hostages deal that would see the return of all remaining hostages, alive and dead.

“We have to stop the war in Gaza immediately. We have to immediately negotiate peace,” he said.

He was to discuss the future of Gaza during afternoon talks with several Gulf leaders.

CRITICISM OF MIGRATION POLICIES

Trump argued that other world leaders should adopt his tough-on-migrants policies, touting his campaign to arrest and deport migrants in the United States illegally, a stance that many countries around the world have viewed skeptically.

He accused the U.N., without providing evidence, of supporting “uncontrolled migration.”

“Europe is in serious trouble. They’ve been invaded by a force of illegal aliens like nobody has ever seen before. Illegal aliens are pouring into Europe,” the president said.

“You need strong borders and traditional energy sources if you’re going to be great again,” he told the world leaders.

Trump, who has cast himself as a peacemaker in a bid to win the Nobel Peace Prize, complained that the United Nations did not support his efforts to end conflicts around the world.

He twinned his complaint with personal grievances about the U.N.’s infrastructure, saying he and first lady Melania Trump were briefly marooned on a U.N. escalator and that his teleprompter was not initially working.

“These are the two things I got from the United Nations – a bad escalator and a bad teleprompter,” Trump said, noting that Melania Trump nearly fell when the escalator stopped abruptly.

Since taking office again, Trump has upended US foreign policy, slashing foreign aid, imposing tariffs on friend and foe alike and cultivating warmer – if volatile – relations with Russia.

At the same time he has sought, so far with only limited success, to solve some of the world’s most intractable conflicts.

Trump is among some 150 heads of state or governments expected to address the chamber this week. He spoke eight months into a second term marked by severe aid cuts that have sparked humanitarian worries and have raised doubts about the U.N.’s future.

According to planning documents reviewed by Reuters, the Trump administration plans to call this week for sharply narrowing the right to asylum, seeking to undo the post-World War Two framework around humanitarian protection.

Trump’s more restrictive stance would include requiring asylum seekers to claim protection in the first country they enter, not a nation of their choosing, a State Department spokesperson said.