The incident had sparked off communal riots across the country and also in Pakistan and Bangladesh in 1992-93.
Muslim organisations have decided to observe "black day" and Hindu outfits, a "day of victory".
A three-tier security cordon has been set up Ayodhya and all its entry points have been sealed to maintain peace on the eve of 21st anniversary of Babri Mosque demolition.
Around 10,000 personnel from state police, Rapid Action Force (RAF) and Provincial Armed Constabulary (PAC) have been deployed to maintain law and order, official sources said.
PAC jawans will also carry out round-the-clock water patrol on river Sarayu to prevent any untoward incident.
All district police chiefs have been directed not to permit any religious event, festival, rallies or meetings on Friday. Goel said vigil would be kept on elements who could disturb communal harmony.
Two dozens CCTV cameras have been installed across Ayodhya city to keep close watch on movements.
Babri Masjid Action Committee (BMAC) convener Zafaryab Jilani has demanded that those guilty of the Babri mosque demolition should be punished and appealed for peace on the 21st anniversary of the incident.
Addressing a meeting of BMAC district units, Jilani said the Prime Minister and UP Chief Minister Akhilesh Yadav will be urged on the December 6 anniversary to initiate action against those guilty of demolition of the mosque in light of Liberhan commission report.
Babri Masjid Action Committee (BMAC)has appealed for peace
Jilani demanded that fresh application be moved in court to include charges of conspiracy of mosque demolition against BJP leader Lal Krishna Advani and others allegedly involved in the incident.
A special prayer would also be held on Friday during which the Muslim community would pray for disposal of all the cases related to the demolition, Jilani said.
He appealed to hold peaceful demonstrations on the anniversary, saying that in districts where demonstrations will be held by BMAC and other secular committees, peace of the state should not be disturbed.
(With agency inputs)