The opposition says a new parliamentary system of government will allow Sarkisian, 63, to maintain huge influence under a new parliamentary system of government.
Serzh Sargsyan, who served as president from 2008 until earlier this year when he stepped down because of term limits, is set to be approved as prime minister on Tuesday.
Pashinyan, a member of Civil Contract party, offered apologies to all the passengers and drivers of the bus and other vehicles, who expressed complaints for being late for work or classes. The parliament where Sargsyan's party has majority will be electing the Prime Minister on April 17.
Several hundred people sat or laid down on pavements on Monday, blocking roads leading to the parliament building and universities.
"Our goal right now is to prevent Serzh Sarkisian from becoming the country's leader for a third time without violence and the use of force", Pashinian said.More news: Bank of America's cost-cutting drive pushes profit to record
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Rallies began on Friday when more than 4,000 people took part.
Armen Sarkisian took over as president from Sargsyan on Monday under a new system in which the president's powers will be weaker and the prime minister will dominate.
Organizers of the anti-Serzh Sargsyan protests that brought downtown Yerevan to a halt today, have called on the global community to urge the Armenian government to halt all undemocratic measures against peaceful protesters.
Before Pashinyan said about the transition to action, "locking" of transport and the Parliament of Armenia.