A US judge has barred federal government officials from liaising with social media companies on removing certain communications from their platforms, in a politically fraught case that addresses tensions between freedom of speech and efforts to curb online misinformation.

Judge Terry Doughty, in Louisiana’s western district, on Tuesday handed down a preliminary injunction that blocks agencies such as the US Department of Justice and the FBI as well as officials including senior White House staff from meeting with social media companies to urge them to delete or reduce content “containing protected free speech” from their platforms.

Plaintiffs including the states of Louisiana and Missouri last year sued the Joe Biden administration, alleging the US government quashed conservative free speech on issues such as the efficiency of masks and lockdowns during the Covid-19 emergency, the integrity of the 2020 presidential election as well as negative content about the president.