Labor minister Lee Jung-sik called on unionized rail workers to call off their planned general strike starting Thursday, urging them to pay attention to public concerns and to withdraw from group action that lacks legitimacy and justification.

At a meeting with officials on Wednesday, Lee criticized the Korean Railway Workers' Union for only being concerned with realizing its demands when it is time to join forces against an unfavorable economic condition.

Stressing that the strike, if proceeded, would adversely impact the economy and public convenience, the minister said a fight that holds the national economy and public livelihoods hostage would not be able to win public sympathy or support.

He said the government will respond sternly to any unlawful activity in line with zero tolerance policy in a bid to minimize damage to the economy and livelihoods.

The union has declared a four-day strike from 9 a.m. Thursday through 9 a.m. Monday, demanding an expansion of KTX high-speed train services to include Suseo Station in southern Seoul, which is the starting station of Super Rapid Train(SRT) service.