One of Spain’s largest worker unions has called for a “symbolic” strike next week by delivery and warehouse workers at Amazon (AMZN) to coincide with Cyber Monday.

The Workers’ Commission reportedly is calling on 20,000 Amazon logistics workers to participate in a one-hour strike on each of three shifts on Nov. 27 and 28. The union seeks to bolster labor safety and human resources staff, as well as garner higher wages that they say are commensurate with the volume of work they are assigned.

“It is symbolic, but it is a first move and we will consider other kind of actions in the future,” Douglas Harper, the Workers’ Commission’s secretary general for Amazon, told Reuters Monday.

Amazon disputed the need for a labor stoppage, saying in a statement sent to Reuters, “Our staff in all of Spain already work in a safe and modern environment with competitive wages and benefits.”

Shopping days like “Black Friday” and “Cyber Monday” are important drivers of fourth-quarter revenue for e-commerce platforms like Amazon. Retailers typically offer significant deals to drive holiday shopping.

Amazon is also facing the prospect of a work stoppage on Black Friday as part of the international “Make Amazon Pay” campaign, led by a coalition of 80 unions responsible for labor actions in 130 countries. That strike would encompass workers in the U.S., England, Italy, and Germany.

“Workers know that it doesn’t matter what country you’re in or what your job title is, we are all united in the fight for wages with dignity and a voice on the job,” global union UNI’s General Secretary Christy Hoffman told The Guardian. “That is why workers around the world are standing up to ‘Make Amazon Pay.'”