Facebook said it pulled a video posted at the social network by US President Donald Trump for fueling violence by supporters who stormed the Capitol building on Wednesday.

"This is an emergency situation and we are taking appropriate emergency measures, including removing President Trump's video," Facebook vice president of integrity Guy Rosen said in a tweet.

"We removed it because on balance we believe it contributes to rather than diminishes the risk of ongoing violence."

YouTube has also removed a Trump video that appeared to be contributing to the mob violence by baselessly challenging the outcome of the recent presidential election, which he lost, according to media reports.