The Trump administration is warning that it might impose more sanctions on Venezuelan officials over President Nicolas Maduro’s push to rewrite the Constitution amid an escalating political crisis with near-daily demonstrations calling for his ouster.

“What President Maduro is trying to do yet again is trying to change the rules of the game,” Michael Fitzpatrick, Deputy Assistant Secretary of State for Western Hemisphere affairs said on Tuesday. “The actions that were taken yesterday may well give us new reasons for considering additional individualised sanctions.”

The warning comes as pressure is building on the Trump administration from the U.S. Congress to act more forcefully to rein in Mr. Maduro. On Wednesday, a bipartisan group of senators said it will introduce legislation providing humanitarian assistance to Venezuela while toughening sanctions against corrupt officials, according to Senate aides who spoke on condition of anonymity. The legislation, a copy of which was obtained by The Associated Press, also instructs the intelligence community to prepare a partly unclassified report on Venezuelan government officials’ involvement in corruption and drug trafficking.

Opposition leaders were gearing up for a major march Wednesday in Caracas, seeking to keep the heat on Mr. Maduro after a month of unrelenting protests. On Tuesday, protesters disrupted traffic in the capital by blocking streets with broken concrete, twisted metal and flaming piles of trash. Police used tear gas to scatter demonstrators as they have almost every day for weeks.

Two people were killed overnight when the bus they were travelling in flipped when it tried to avoid a barricade set up by protesters, according to opposition activists who live near the accident site in Carabobo state. A third person was killed during a looting incident at a shop in the industrial city of Valencia. The deaths bring to 32 the number of people who have died in the unrest over the past month.