In the EDM, MP Gerald Kaufman slammed Bestway subsidiary Bestway Northern for dismissing two of his constituents on the grounds they were not permitted to work legally in the UK.
Kaufman claimed to have evidence that they could have worked until an appeal with the UK Border Agency was heard.
The EDM, which as The Grocer went to press had not been backed by any other MPs, accused Bestway Northern of allegedly conducting a "show trial of two employees" and treating its staff like serfs. It branded the company "duplicitous tyrants".
A Bestway spokesman said: "Bestway complies with employment and immigration laws rigorously. It is concerned about the tone of Mr Kaufman's slur on its reputation and that he has wasted parliamentary time. It challenges him to waive privilege and make a similar statement outside parliament."