WASHINGTON (AP) — The United States is ordering relatives of American diplomats to leave the Venezuelan capital ahead of a polarizing vote planned for Sunday to start rewriting the country's constitution.

A demonstrator holds a Venezuelan national flag at a blockade during a rally against Venezuelan President Nicolas Maduro's government in Caracas, July 18, 2017. Thomson Reuters

WASHINGTON (AP) — The United States is ordering relatives of American diplomats to leave the Venezuelan capital ahead of a polarizing vote planned for Sunday to start rewriting the country's constitution.

The State Department says it's also allowing U.S. government workers to depart the embassy in Caracas and limiting the movement of those who stay.

An updated travel warning also urges American citizens not to travel to Venezuela due to social unrest and violence.

The ordered departure comes three days before President Nicolas Maduro's government plans to hold a vote for an assembly tasked with overhauling the country's charter. Maduro's opposition says the election rules are rigged to strengthen his hold on power.

The U.S. has been urging Maduro to cancel the vote and threatening more U.S. sanctions if occurs.