When Cuban President Raúl Castro was asked his view of the U.S. presidential election, he did what foreign leaders usually do.

He did not answer the question.

Castro responded, "I cannot vote in the United States" at a news conference Tuesday with President Barack Obama in Havana.

But other foreign leaders are breaking with tradition of not taking sides in other countries' elections.

Most of those who are speaking out are criticizing the leading Republican presidential candidate, businessman Donald Trump.

Mexican President Enrique Pena Nieto compared the language of Trump to Adolf Hitler and Benito Mussolini.

Trump has called for Mexico to pay for a new wall between the two nations. He also said Mexico is "sending people that have lots of problems... they're bringing drugs, they're bringing crime. They're rapists. And some, I assume, are good people."

Pena Nieto responded in an interview with Mexico's Excelsior newspaper. "That's the way Mussolini arrived and the way Hitler arrived," he said.

In England, Parliament debated a resolution to ban Trump from entering the country. The debate came after Trump called for a temporary ban on all Muslims entering the United States.

Parliament ended up not voting on the Trump resolution. But British leaders still criticized him.

"I think his remarks are divisive, stupid and wrong," said British Prime Minister David Cameron.

After the March 22 terrorist attacks on Brussels, Trump tweeted a link to remarks he made in January, calling the Belgium city a "hell hole."

"Time & time again I have been right about terrorism. It's time to get tough," he tweeted.

When the New York Times reached Brussels Mayor Yvan Mayeur for a response, his office wrote, "We don't react to Mr. Trump's comments. Have a nice day."

The day before the terrorist attacks, Trump said he favors reducing the U.S. involvement with NATO. NATO is a 28-nation coalition that works for the security of its member nations.

Trump has argued throughout his campaign that other nations besides the U.S. should be paying more to defend Europe and Asia.

Ana Palacio is a former Spanish foreign minister. She expressed concerns about Trump's views in a recent interview with Politico.

"The opportunism, unreliability and amorality that we have seen during the [Trump] campaign would be damaging for the world in general and hurt Europe in particular," she said.

James Thurber heads the Center for Congressional and Presidential Studies at American University in Washington D.C. He said it is "highly unusual" for foreign leaders to criticize a candidate for the presidency, even before he has won his party's nomination.

Thurber just returned from Turkey, where many already have negative views of the United States

"But they are appalled at what Donald Trump is saying about Muslims," he said.

Some foreign leaders praise Trump

Trump is getting some support from abroad, particularly in Russia. He called Russia's President Vladimir Putin a strong leader and said he "would probably get along with him [Putin] very well."

Putin, in return, praised Trump as "a bright and talented person."

Victoria Zhuravleva is a Moscow-based expert on U.S.- Russian relations. She said the U.S. has criticized Russia and Putin over the last two years.

"So, when you hear something that is not so critical and even friendlier towards your country it's like, ‘Thank God. There's one person we can talk to, Donald Trump.'" She told Reuters.

Trump is also getting praise from some anti-immigration leaders in Europe. They agree with Trump that immigration from the Middle East should stop.

Jean-Marie Le Pen is the former head of the French National Front Party, which wants to limit immigration.

He tweeted, "If I were American, I would vote Donald Trump,"

Bruce Alpert reported on this story for VOA Learning English. Hai Do was the editor.