Fighting the Congress in the family pocket-borough of Kadapa in prestigious by-elections, Y S Jagan Mohan Reddy today ruled out going back to the party, saying he cannot "throw his core values" for the sake of "power and position".

Nearly six months after exiting the Congress alleging "humiliation", the son of late Andhra Pradesh chief minister Y S Rajasekhara Reddy faces his first major political test on May 8 when the by-polls for Kadapa Lok Sabha which he vacated in November, 2010 will be held.

Pulivendula assembly seat, which was represented by his mother Vijayalaxmi, is also going to by-polls on May 8.

Both vacated their seats after they quit the Congress.

38-year-old Jagan, who had openly revolted against Sonia Gandhi, termed the by-polls a fight between the "self-respect of Andhra Pradesh" and "injustice of Delhi."

"This is a fight between credibility and opportunism (of Delhi). This is a fight between YSR district (Kadapa) and Delhi," Jagan told PTI.

Jagan, who launched YSR Congress recently, is giving a tough fight to ruling Congress candidate and health minister D L Ravindra, a bete noire of his late father, and TDP's M V Mysura Reddy in Kadapa. Jagan's mother is taking on late YSR's brother Y S Vivekananda Reddy in Pulivendula.

With both Jagan and Congress claiming to be the real heirs to YSR legacy, the electoral contest in Kadapa and Pulivendula promises to be a political potboiler.

He also criticised Chief Minister N Kiran Kumar Reddy for deploying almost the entire cabinet in Kadapa to "ensure his defeat" and made it clear that YSR Congress is here to stay to carry on the legacy of his late father.

"The question does not arise at all. When did I ever ask for positions? I cannot throw my core values into a dustbin as some do for the sake of power and position. What kind of a politician that would make me then?" Jagan asked.

He was replying to a question on whether he was ready for a rapprochement with the Congress in the future if Gandhi promised him a position in the party or in the government.

Jagan said he and YSR Congress will make sure that all welfare measures implemented by the late Reddy and will work for "the maximum benefit of my people and my state once I am blessed with those numbers."