Starbucks and the union had temporarily agreed to collective bargaining over dress code changes as part of ongoing negotiations for a new contract. In December, a bargaining session with the company failed to produce better wage gains.

More than 2,000 Starbucks baristas at 120 U.S. stores have gone on strike since Sunday to protest a new company dress code.

Hundreds of Starbucks workers have walked off the job at over 100 U.S. stores this week in a strike that's protesting a new dress code that went into effect this week. The big picture: Axios' Kelly Tyko notes the Seattle-based cofee giant is trying to revitalize the brand amid sluggish sales by returning to its roots with a new design Starbucks says provides "simplified color options that allow our iconic green apron to shine,