The US State Department has denied accusations that three of its diplomats in Venezuela recruited students to lead opposition protests.
The consular staff are said to have used visa visits to universities as cover for promoting demonstrations to students.
The three have been given 48 hours to leave Venezuela.
The State Department has called the allegations “baseless and false” adding that Washington supports free expression and peaceful assembly in Venezuela and around the world.
Student demonstrators have promised to stay in the street until President Nicolas Maduro resigns, but the former bus driver has vowed not to cede even a “millimeter” of power.
Opposition leader Leopoldo Lopez called for students to march with him to the centre of Caracas today.
Lopez is wanted on charges including murder and terrorism. He said he would then hand himself in.
The Caracas protests have been limited to mostly upscale areas. There has been no evidence that Venezuelans would join them en masse or that Maduro could be forced from power.