Samsung  says the strike would not affect production.   / Photo: Reuters

A union representing tens of thousands of workers at Samsung Electronics in South Korea said Wednesday it would extend a three-day strike indefinitely in a bid to force management to negotiate.

The strike is the biggest labour action in the tech giant's history and steps up pressure on the chipmaker's management, who last week predicted a huge second-quarter operating profit increase.

"(We) declare a second indefinite general strike from July 10, after learning that the management has no willingness to talk," the National Samsung Electronics Union said in a statement.

More than 5,000 members stopped working Monday for what was meant to be a three-day strike, part of a long-running battle over pay and benefits.

'No effect on production'

The move follows a one-day walkout in June, the first such collective action at the company, which went decades without unionisation.

The union has more than 30,000 members—more than a fifth of the company's total workforce.

Samsung told AFP Wednesday that the strike would not affect production.

"Samsung Electronics will ensure no disruptions occur in the production lines," a spokesperson told AFP, adding the company "remains committed to engaging in good faith negotiations with the union."

'Management will suffer'

But the union said it had confirmed "clear disruption in production", and added that the longer the strike goes on, "the more the management will suffer."

"Eventually, they will kneel and come to the negotiation table. We are confident of victory," it added in a statement, urging more workers to participate.

Samsung Electronics is the world's largest memory chipmaker and accounts for a significant chunk of the global output of the high-end chips used in generative AI.

But as semiconductor factories are highly automated with low demand for actual manpower, it is likely the strike will not have a major impact, Avril Wu, an analyst at Taipei-based research group TrendForce, told AFP.

Locked negotiations

"Even if the strike is extended, the current assessment is that there will still be no significant impact," Wu said.

The union has been locked in negotiations with management since January, but the two sides have failed to narrow their differences.

The union's demands, newly released on Wednesday, include a 5.6 percent pay raise for all members, transparent performance-based bonuses, compensation for financial losses incurred due to the strike, and a guaranteed day off on the union's founding day.

Whether the strike hits production "depends on various factors, (such as) duration of the strike, accordingly lost days of production and recoup strategy", said Neil Shah, research vice president at Counterpoint Research.

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