"As we see, [Nikol] Pashinyan has not tendered his resignation. Therefore, Armenian citizens have the right to protest peacefully from now until 17:00 [13:00 GMT]," Ishkhan Sagatelyan, spokesperson for opposition party Dashnaktsutyun (Armenian Revolutionary Federation), said in a televised address.
He called on Armenians to respect the law and ignore provocation, and also urged law enforcement agencies to protect citizens' right to peaceful rallies.
"Nikol, you will step down anyway so leave peacefully. Take care of our people, state, and statehood, do not undermine the life of our country. Your departure is vitally important for our people and the state," Sagatelyan added.
He earlier warned that if Pashinyan fails to step down by 08:00 GMT on Tuesday, rallies would start across the country.
On 9 November, the leaders of Russia, Armenia, and Azerbaijan released a joint statement on the cessation of hostilities in Nagorno-Karabakh in the wake of the six-week-long conflict. The warring sides have agreed to cease fighting in the occupied territories, as well as exchange prisoners and the bodies of dead soldiers. Russia has deployed 1,960 peacekeepers to monitor the truce.
The ceasefire agreement was lauded as a victory by Baku, sparking protests in Yerevan calling for the deal to be scrapped and Pashinyan's resignation.