A former opposition presidential candidate rejected accusations Tuesday that he is an opportunist who switches parties ahead of elections, claiming he has followed only one political course.

Chung Dong-young, a former three-term lawmaker and presidential candidate of what is now the main opposition New Politics Alliance for Democracy, left the party in January to create a new left-leaning party ahead of the April 29 parliamentary by-elections. On Monday, he announced his bid for one of the four seats up for grabs -- in district B of Seoul's Gwanak District.

NPAD immediately accused him of being a "migratory bird," switching parties according to his own political interests, saying he would only split the opposition vote in favor of the ruling Saenuri Party.

Speaking on local radio, Chung rejected the accusations.

"Birds that migrate from their political course should be banished, but it isn't right to call a politician who has been following one course for the weak and the working class a migratory bird," he said. "What's important to a politician is his political course. I am a politician who has been flying his exact course."

In South Korea, new parties have often formed or merged with existing parties in the run-up to elections to boost their chances of winning. A total of 177 parties have been registered with the National Election Commission  since data collecting began in 1963, according to the NEC. Currently, 17 of those parties remain. (Yonhap)