The proposed yatra was earlier banned by the state government.
Home department officials said that under no circumstance would the Vishwa Hindu Parishad event be allowed to take place.
"Other than deputing extra security forces in the region, barricading the routes is an option we are exploring," a senior official told IANS.
The government has decided to deploy 10 companies of the Rapid Action Force (RSF) and 12 companies of the Provincial Armed Constabulary (PAC) in the region.
Inspector General of Police Raj Kumar Vishwakarma told IANS that orders have been issued to prevent people from other states from reaching Ayodhya.
An elaborate security plan is being chalked out to foil the event, set to begin Aug 25.
The VHP has refused to back off, saying the yatra is part of Hindu beliefs and tradition.
Slamming the government for the clampdown, Swamy Chinmayanand accused Chief Minister Akhilesh Yadav of working under pressure from his party's Muslim leaders.
He came down hard on Urban Development Minister Mohammad Azam Khan, accusing him of "arm-twisting the Samajwadi Party leadership into banning the 84-kosi parikrama".
Uttar Pradesh Public Works Department Minister Shivpal Yadav refuted the charges and said the government was committed to maintain communal harmony.
--IANS (Posted on 21-08-2013)