Starbucks CEO Brian Niccol announced Thursday that the coffee giant will close underperforming stores in the U.S., cut 900 non-retail partner roles and freeze many open positions as part of its ongoing turnaround strategy.

Niccol said in a letter to employees that during a review of Starbucks’ North America coffeehouse portfolio, the company identified locations that were "unable to create the physical environment our customers and partners expect" or where it does not see a "path to financial performance."

Niccol didn't disclose how many locations would be impacted, but said employees at the affected stores will be notified this week. Starbucks also plans to inform employees whose roles are being eliminated on Friday.

"These steps are to reinforce what we see is working and prioritize our resources against them," Niccol said. 

Just a year into the job, Niccol has said the company is "ahead of schedule" in its turnaround, but told employees Thursday that much more work remains to build a more resilient company. That includes carefully managing costs and focusing on the key areas that drive long-term growth.

Still, Niccol noted that "early results from coffeehouse uplifts show customers visiting more often, staying longer, and sharing positive feedback." 

This is a developing story. Check back for updates.