Samsung Electronics workers in South Korea have started a four-day strike, as the latest chapter in a months-long conflict over wages.

The National Samsung Electronics Union (NSEU) — the biggest worker union in the country — started its strike on August 15, according to Reuters. The NSEU has been pushing for a wage increase and a more favorable bonus structure since the start of the summer. It conducted a one-day-walkout in June, marking the first labor strike in Samsung Electronics' history. Then in July, NSEU workers went on strike indefinitely, before returning in early August. 

In a statement to Reuters, Samsung Electronics said that it does not expect the latest four-day strike to have a significant impact on production, and that it's hoping to resume negotiations with the NSEU soon. The company also claimed that the union timed the strike to coincide with a national holiday on August 15, to ensure that there wouldn't be enough backup workers to keep production lines moving. In the meantime, the union has vowed to continue holding strikes unexpectedly until an agreement is reached with the company.