The Left leader said he now expected the BJP to pursue the "Hindutva policies" more vigorously.
"Narendra Modi may become more dictatorial. It is not a positive sign for Indian democracy," Reddy told PTI.
The CPI leader said although the Congress improved its tally in Gujarat, the ruling party (BJP) could overcome "anti-incumbency", and that it was a pity that "secular forces" could not defeat the saffron party.
"Anti-BJP forces should come together to fight against communal forces," he said, adding that an electoral understanding between the Left and such parties may not be easy to forge at the national level.
More From This Section
The veteran communist leader also had a word of praise for newly-appointed Congress president Rahul Gandhi, saying he did a good campaign and could clearly carry the "message of anti-communal forces" during campaigning.
When asked if he expects Gandhi to emerge as a "good leader", Reddy said it depended on how he was going to implement reforms inside the party.
The Left leader said the Congress should come "closer to poorer sections of people" and get rid of the "brand of being pro-corporate".