Demonstrators blocked streets in the centre of Yerevan in opposition to a change of government that will see Sarkisian maintain huge influence.
Young people in small groups have been blockading transport routes in the streets; garbage bins are used as barricades.
On Monday morning, opposition head of Armenia's Civil Contract Party member and National Assembly (NA) "Way Out" Faction, Nikol Pashinyan and his supporters have blocked Baghramyan Avenue in Yerevan.
On the eve of April 15, speaking at the France Square, where non-stop protests against the Serzh Sargsyan nomination had been passing for four days, Pashinyan called for civil disobedience. Pashinyan was the first to lay down in front of a bus, while activists chanted the movement's slogan: "Take a step, reject Serzh!".
Armenia Police: Twenty-nine protesters detained in Yerevan clashes
The Republican Party of Armenia and the Dashnaktsutyun party, which are in the ruling coalition, nominated the former president of the country Serzh Sargsyan for the post of prime minister. As of 16:20 Yerevan time, the protesters are still in the radio building. The latter require that they do not restrict the right to movement of citizens.
There were media reports that Tuesday's NA special session to elect the PM would not be convened in the parliament building.
Serzh Sarkisian had promised in 2014 that he would "not aspire" to the post of prime minister if Armenia switched from a presidential to a parliamentary system as a result of the referendum.
JAMnews continues to follow events as they develop.
- Eurocontrol warns airlines of 'possible military action' in Syria
- Shenmue I and II are coming to current gen platforms
- Inflation slows in 1Q on fees-free policy
- Sony India extends its Headphone and Speaker line-up for 2018
- Caterpillar Inc. (CAT) EPS Estimated At $2.04
- IMO agrees strategy for cutting carbon dioxide emissions in shipping
- Climate protest lawyer sets himself on fire
- James Comey lets rip on Trump in first televised interview since firing
- Sonam Kapoor and Anand Ahuja wedding: Farah Khan to supervise sangeet?
- Traders Buy Financial Select Sector SPDR Fund (XLF) on Weakness