President Donald Trump urged Venezuela’s military to drop their support for President Nicolas Maduro and allow humanitarian aid into the country.

“You will find no safe harbor, no easy exit and no way out. You’ll lose everything,” Trump said at a Monday night rally in Miami, warning Venezuela’s armed forces to suspend their loyalty to Maduro.

The crowd at Florida International University was made up of mostly of immigrants from Venezuela and Cuba, Reuters reports. More than 100,000 Venezuelans and Venezuelan-Americans live in South Florida, the largest concentration in the country.

Trump offered strong backing for Venezuelan opposition leader Juan Guaido, who declared himself the interim president after rejecting Maduro’s election to a second term last year as illegitimate. Trump called on the military to turn their support to Guaido and allow U.S. aid to be let into country, after Maduro ordered a blockade on the border.

“You must not follow Maduro’s orders to block humanitarian aid and you must not threaten any form of violence against peaceful protesters, opposition leaders, members of the National Assembly or President Guaido and his family,” Trump said.

He also accused Maduro of following orders from Cuba and being a “Cuban puppet.”

Maduro responded by calling Trump’s speech “Nazi-style” and accusing the U.S. President of acting as though he owned Venezuela, according to Reuters.

Maduro has depicted U.S. aid as a part of a ploy to stage a coup, repeatedly denying that the country is in need of help despite high rates of poverty and food shortages.

More than three million Venezuelans have fled the country in recent years, according to the U.N., and the number continues to rise.

Meanwhile, shipments of aid have been stockpiled and held at collection points in Brazil, the Colombian border town of Cucuta, and a Caribbean island.

In line with Maduro’s insistence that Venezuela is not in need of foreign help, the regime also said that it would be sending 20,000 boxes of food aid to Colombia, citing poverty statistics there.

After the rally, Trump continued the discourse on Twitter, calling on the Maduro regime to “end this nightmare of poverty, hunger and death.”

Last week, Guaido announced that his team had delivered its first round of aid, consisting of nutritional supplements for pregnant women and children, amid objections from Maduro. He did not say where the aid was from.

Trump’s address came a day after Senator Marco Rubio visited the Venezuela-Colombia border and said the U.S. was determined for aid to enter the country despite Maduro’s orders.

Much of the European Union and many of Venezuela’s neighbors have joined the U.S. in backing Guaido, while Maduro retains the support of China, Russia and Turkey.

Write to Hillary Leung at hillary.leung@time.com.