Addressing an election rally in this Andhra town, she appealed to people to reject TDP-BJP, saying a vote for the alliance will be a divisive vote that will spread prejudice and hatred among people.
"A vote for TDP will only strengthen communal forces and greatly damage our secular fabric," she said.
The Congress chief said TDP and BJP were old friends. She recalled that TDP did not leave BJP "even at the time of horrific happenings in Godhra in 2002". "Many parties walked away from NDA but not the TDP," she said.
Cong is the only party that always stood for secular values and principles:Sonia
Sonia Gandhi claimed that Congress is the only party that always stood for secular values and principles and never ever compromised with the communal forces.
"It is these very values and principles that kept our country together and for these values and principles Indira Gandhi and Rajiv Gandhi became martyrs."
The Congress leader claimed that Congress is the only party committed to the cause of social justice as it believes that the keys of political power must be with the weaker sections of the society like Dalits, tribals, backward classes, minorities and women who were long deprived and neglected.
She also criticised YSR Congress party for exploiting the name of late chief minister Y.S. Rajasekhara Reddy.
"YSR was a valued and loyal member of our party. The Congress party gave him an opportunity to serve the people and he worked hard and implemented the policies of Congress party," she said.
"People who exploit his name choose to ignore the fact YSR dedicated his entire career to the Congress party. It is the Congress party which gives all of us including myself an identity," she added.