The White House said Monday it was "concerned" about violent protests in the Venezuelan capital of Caracas that have left at least a dozen dead.

"We are working to urge calm and encourage a genuine dialogue among all Venezuelans," White House press secretary Jay Carney said.


Carney also criticized Venezuelan President Nicolás Maduro for accusing Washington of plotting with opposition protesters.

"Rather than trying to distract from its own failings by making up false accusations against the United States, which the government there has, the Venezuelan government ought to focus on addressing the legitimate grievances of the Venezuelan people," Carney said.

Earlier this month, Venezuela expelled three U.S. diplomats.

Carney intimated that the President Obama would not engage in a requested dialogue with Maduro.

"He should focus instead on a dialogue with the Venezuelan people, because that is what is at issue here," he said. "This is not about the United States."

Carney also called on the Venezuelan government to release detained prisoners and stop impeding the work of independent journalists. The government has imprisoned protest leader Leopoldo López as well as a number of student protesters.

"Freedom of expression and peaceful assembly are universal human rights," Carney said. "They are essential to a functioning democracy, and the Venezuelan government has an obligation to protect these fundamental freedoms."

The sustained demonstrations in Caracas are a serious challenge to Maduro, who is looking to extend the legacy of longtime Venezuelan leader Hugo Chávez.