Unionized workers of Seoul Metro, the operator of Seoul subway lines No. 1-8, will stage a second strike on Nov. 22 in protest of the company's workforce downsizing plans.

The Seoul Metro labor union on Tuesday announced it will hold a press conference the following morning in front of the Seoul City Hall in Jung-gu, central Seoul, and disclose the plans to its forthcoming walkout.

The announcement follows the union's temporary strike held Thursday-Friday, as the workers' body failed to reach an agreement with the company in relation to the reduction plan.

"We have constantly urged Seoul city and the company for changes in positions and negotiation following initial warning strike (last week), but they suddenly repositioned to take hardline measures," the union said, adding, "They have failed to offer any plans against the possible vacancy of on-site safety personnels."

The union is expected to reveal the exact plans during the press conference on Wednesday.