Widely expected to roll back at least the lower class passenger fare hike proposed by Trivedi in the Railway Budget, Roy, 57, was sworn in as cabinet minister at a special but brief ceremony by President Pratibha Patil at the Rashtrapati Bhawan.
He was currently serving as Union Minister of State for Shipping and had earlier served as Minister of State in the Railway ministry before Trivedi took over last July.
The ceremony was attended by Vice President Hamid Ansari, Prime Minister Manmohan Singh, the UPA chairperson and cabinet ministers including ministers of Tinamool Congress.
Trivedi was forced out by Trinamool Congress after he incurred the wrath of party chief and West Bengal Chief Minister Mamata Banerjee who was opposed to his proposal to increase fares in the railway budget last Wednesday. Trivedi resigned on Sunday.
The Congress leadership caved in to the Trinamool demand for replacing him with Roy. On Monday, Mamata had indicated that the hike in the lower class fares proposed in the Railway budget may be rolled back.