The Trump administration has frozen all Venezuelan government assets in a significant escalation of tensions with socialist leader Nicolás Maduro. It places Washington’s trade relations with the South American country on a par with Cuba, Syria, Iran and North Korea.

The ban on Americans doing business with Venezuela’s government takes effect immediately.

“All property and interests in property of the Government of Venezuela that are in the United States ... are blocked and may not be transferred, paid, exported, withdrawn, or otherwise dealt in,” the executive order says.

The order, signed by President Trump on Monday, cited Maduro’s continued “usurpation” of power and human rights abuses by those loyal to him.

While the order falls short of an outright trade embargo, it represents the most determined US action to remove Maduro since the Trump administration recognised opposition leader Juan Guaidó as Venezuela’s rightful leader in January. As such, it places Venezuela on par with adversaries such as Cuba, Syria, Iran and North Korea, who have also come under strident US measures.

Previous sanctions have targeted dozens of Venezuelan government insiders as well as the South American nation’s oil industry, the source of almost all of its export earnings.

As part of the executive order, Americans will be banned from engaging in transactions with anyone determined to be assisting Maduro or his government. The same Maduro supporters will also be banned from entering the US.

Exceptions will be allowed for the delivery of food, medicine and clothing. Transactions with Venezuela’s still sizeable private sector do not appear to be affected either.

China and Russia have continued to back Maduro, prompting US national security adviser, John Bolton, to warn the two countries on Monday against doubling down in their support for him.

On Tuesday Bolton, and US Commerce Secretary, Wilbur Ross, represent the United States at the International Conference for Democracy in Venezuela.

The conference is being attended by representatives from more than 50 nations that recognise Guaidó as Venezuela’s president and consider Maduro’s re-election last year to be fraudulent.

Moments after the executive order was announced, Bolton tweeted that he was looking ahead to what he hopes will be a “productive” day in Lima.