Belarusian protesters were due to stage a new march on Sunday against strongman Alexander Lukashenko in defiance of authorities’ threat to open fire in an increasingly dangerous standoff between the opposition and the regime.

The ex-Soviet nation of 9.5 million has been gripped by historic protests after Lukashenko claimed victory in August 9 elections over Svetlana Tikhanovskaya, a 38-year-old popular opposition candidate.

The protest movement has kept up a series of large-scale demonstrations for the past two months, with around 100,000 people or more taking to the streets every Sunday.

The new demonstration in the capital Minsk is set to take place after Tikhanovskaya, who was granted shelter in EU member Lithuania, said Lukashenko must quit power before October 25, warning he would otherwise face a crippling general strike.

Tikhanovskaya, who maintains she was the true winner of the August polls, also said Lukashenko must release political prisoners and halt the “state terror” unleashed by authorities against peaceful protesters.

Since the start of the post-election crackdown in which several people died and thousands have been arrested, harrowing accounts have emerged of abuse in Belarusian jails. Many said they had been tortured, beaten and humiliated in detention.

Police have acknowledged using water cannon and stun grenades against demonstrators but the use of live ammunition would mark a major escalation in the more than two-month standoff between Lukashenko and protesters.

Last week police claimed that protests were becoming more radicalised and warned that law enforcement would use lethal weapons “if necessary”.