She also dismissed the Third Front as a "weak front" and said the "country will not be benefited from it."
"We will put our entire strength to prevent Narendra Modi from becoming the Prime Minister. It is in interest of the country to prevent the BJP from coming to power (in the next elections)," Mayawati told reporters outside Parliament.
She claimed that minority community members were apprehensive about Modi.
"If Modi wins, it will give a boost to the communal forces in the country," the BSP supremo said, adding BJP is not trustworthy as "it says something and does something else".
On the six pending anti-corruption bills, she said though "we support the bills they should have come much earlier. Now the government, which itself is involved in deep corruption, is trying to change its image through the bills."
Slamming Mayawati for her remarks on Modi, senior BJP leader Ravi Shankar Prasad said several people have attempted to stop Modi and BJP from coming to power in the last 25 years.
"But the people of the country did not give any heed to them. Wait for two months and we will come to know who has the blessings of the people," he told reporters outside Parliament.