The prime minister is set to address the gathering after the ceremony.
Prime Minister Narendra Modi reached the Ram Temple at Ayodhya as the rituals for the consecration ceremony began at noon on Monday.
Wearing a white and gold dhoti-kurta, the prime minister walked to the temple with a offering in hand and climbed up the stairs to entre the grand structure.
After entering the temple, the prime minister passed the offering -- a silver chhatra (umbrella for the idol) and a red chunni -- to a priest.
The prime minister then took ‘sankalp' for the consecration ceremony and joined the rituals along with RSS chief Mohan Bhagwat.
After the ceremony, PM Modi will address a gathering and visit Kuber Tila.
The prime minister offered flowers at the feet of the idol and performed an aarti.
The prime minister also performed a "dandavat pranam" to the idol after the consecration ceremony.