A brutal boss cancelled their employee's annual leave after they called in sick despite the worker making it clear the time-off related to their mother's cancer diagnosis.

The part-time team member, who lives in Perth, is due to fly to America on Friday, but has been forced to exchange in a battle with their line manager over the annual leave request.

Opening up about the ordeal to SkyNews.com.au, the Coles employee, who did not want to be named, said: "This whole situation has put a lot of stress on me, and I can’t focus on anything productive at the moment as every minute is making me anxious."

The nightmare began when the employee requested leave from November 7 to 21 in order to fly to California and spend time with their mother, who is currently undergoing chemotherapy treatment.

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