Washington DC - Two environmental protesters dumped red powder on the protective case holding the US Constitution on Wednesday, prompting a shutdown at the National Archives in Washington.

"We all deserve clean air, clean water... and a liveable climate," one of the protesters says in a video of the incident posted on social media, calling for an end to government subsidies for fossil fuels and for President Joe Biden to declare a climate emergency as global heating worsens.

On public display under thick bulletproof glass in a climate-controlled case, the nation's founding document did not appear to be damaged.

The National Archives said it was closing the building's rotunda, where the constitution and other historic documents are on view, for the rest of the day.

"The National Archives Rotunda is the sanctuary for our nation's founding documents," chief archivist Colleen Shogan said in a statement. "They are here for all Americans to view and understand the principles of our nation."

"We take such vandalism very seriously and we will insist that the perpetrators be prosecuted to the fullest extent of the law."

In recent years, environmental protesters, especially in Europe, have taken to museums, often targeting glass cases but not the actual artworks themselves.

Last month, protesters calling for "healthy and sustainable food" hurled pumpkin soup at the bullet-proof glass protecting Leonardo da Vinci's Mona Lisa in Paris.

In the video of Wednesday's incident, security guards are seen arresting the protesters and clearing out the building, a major tourist attraction in the US capital.

The National Archives confirmed the arrests in a statement.

"We don't want the end of civilization, but that's the path we're currently on," Declare Emergency, a climate protest group, said on social media claiming responsibility for the action.