The warning comes as Cuba was plunged into darkness by an island-wide power outage.

The war powers resolution from Democratic Sens. Ruben Gallego of Arizona, Tim Kaine of Virginia and Adam B. Schiff of California would direct the president to “remove the United States Armed Forces from hostilities within or against Cuba,” according to text released Friday.

Cuba says Cubans abroad – including Miami – can invest and own private businesses as talks with the US advance.

Dramatic footage appears to show protester on the ground after alleged gunfire as crowds attack Communist Party building in Cuba, chanting 'Freedom!' amid crisis.

The United States has told Cuba that for meaningful progress to be made in negotiations, President Miguel Díaz-Canel must step down, said people familiar with the talks.

The Trump administration seeks to remove a significant obstacle to progress in negotiations.