Speaking to reporters here, "We will not allow the division of Andhra Pradesh. Why should Andhra be divided?."
Rajagopal and 130 legislators from the state Assembly had submitted their resignations in protest against the Central government's nod to creation of a separate Telangana state.
"The situation in Andhra Pradesh is very disturbing," Rajagopal said voicing his concern.
"Now I have decided to join the movement (against division of the state). Hyderabad is the mother and the 22 districts of Andhra Pradesh are her children. We will not betray our mother," he said.
"I wish that peace prevails in the state and that Telugu-speaking people the world over and in Andhra Pradesh come and demonstrate their unity," the Congress MP added.