Story highlights Economic sanctions could compound Venezuelan's misery

US biggest export market for Venezuelan oil

(CNN) US President Donald Trump described Venezuelan President Nicolas Maduro as a "bad leader" and an aspiring "dictator" on Monday, and threatened to take "strong and swift economic actions'' if Maduro goes ahead with plans to rewrite the country's constitution.

Maduro is pushing a plan to create a new Constituent Assembly with the power to rewrite Venezuela's constitution. The body would replace the National Assembly, which is currently controlled by Maduro's opponents. A nationwide referendum is due to be held on the issue at the end of the month.

On Sunday 7.2 million opposition supporters , almost a third of the country's registered electorate, voted in an unofficial non-binding referendum to reject the proposed assembly. The opposition is also calling for fresh elections before Maduro's term ends in 2019.

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"Yesterday, the Venezuelan people again made clear that they stand for democracy, freedom, and rule of law," Trump said in a statement released Monday.

"Yet their strong and courageous actions continue to be ignored by a bad leader who dreams of becoming a dictator. The United States will not stand by as Venezuela crumbles. If the Maduro regime imposes its Constituent Assembly on July 30, the United States will take strong and swift economic actions," Trump said.

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