Pressure is growing on Lebanon's government after a protest campaign spurred by a rubbish crisis gave political leaders a deadline to meet their demands.
"Your time is up," the You Stink campaign behind Saturday's huge demonstration in central Beirut said on Facebook.
At the mass rally, You Stink threatened to escalate its protest movement if the government does not meet the demands by Tuesday evening.
The ultimatum calls for a sustainable solution to a rubbish crisis that flared in mid-July, the resignation of Environment Minister Mohammad Mashnuq and new elections to replace a parliament in power since 2009.
On Saturday, tens of thousands of protesters gathered in the capital's iconic Martyrs Square to express their rage at endemic corruption in the government and lack of basic services, including power and water.
Men and women of all ages flooded the square in a rare example of non-partisan mobilisation in the divided republic.
You Stink organiser Lucien Bourjeily called the rally "a really big victory".
"It also shows us that it's a big responsibility for us. We have to achieve the demands that we have set out," he told AFP.
Newspapers on Sunday noted that for once the protest was organised by civil society instead of the divided political elite.
There has been no official government response to the ultimatum.
But Parliament Speaker Nabih Berri said the demands could only be met through "the preservation and activation of the government".
Speaking at a rally of his largely Shi'ite Amal movement, Berri also called for fresh dialogue to discuss the presidential vacuum and the work of the cabinet and parliament.
Druze leader Walid Jumblatt tweeted that Saturday's protest "expressed the true pains of the Lebanese citizen... that no party dares to respond to".
Political rivalries have undermined change in Lebanon for years.
The 128-seat parliament has twice extended its mandate since 2009, and has been unable to elect a president since May 2014.
Any effective work by the cabinet has been paralysed.