Jim Reeves, from the Communication Workers' Union, says the argument to close 70 Crown Post Offices is flawed because the business is profitable.
He spoke to ITV News Central outside the Kings Heath branch in Birmingham as staff went of strike this morning.
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Patchy fog likely, perhaps with some drizzle tomorrow.
Dry with variable cloud overnight. Breezy but mainly dry Thursday.
In the West Midlands almost seven out of every 10 people are overweight or obese, whilst 81% are unaware about the link with cancer.