The High Court in Lusaka issued press accreditation cards to foreign media outlets last week but later withdrew them.
“We initially withdrew the cards to activate the barcodes in good faith (but) unfortunately your applications have now been rejected,” Neto Zulu, senior assistant registrar at the court, told AFP and other media outlets.
A large number of police officers were on duty at the court, where Hichilema was due to enter a plea to the treason charges.
President Edgar Lungu has denied allegations of a crackdown on dissent in Zambia.
He invoked emergency powers in July, increasing police powers of arrest and detention after he blamed opposition parties for a string of arson attacks.
Hichilema, who narrowly lost last year’s presidential election, has been in custody since April over an incident when he allegedly failed to give way to Lungu’s motorcade.
A lawyer from Hichilema’s United Party for National Development (UPND) told AFP that the party expected the charges to be dropped and for Hichilema to walk free later Monday.
os/bgs/txw
Download our app and read this and other great stories on the move. Available for Android and iOS.