Meanwhile, a spokesperson for Big W said the timing was mere coincidence and that 90 per cent of staff had voted in favour of the new agreement in a ballot held last month.

The clause that has been removed stated: "no existing full time or part time employee shall be forcibly made redundant".

RAFFU secretary Josh Cullinan called the closure announcement "a slap in the face for the communities which have built the success of the Woolworths Group over many decades".

"The new agreement deleted a fundamental workplace protection which prohibited Big W from forcibly making workers redundant," he said.

"It is with that restriction gone that Big W can close stores - workers were never told the restriction would be deleted."

"It is the obligation of the employer to explain any major changes to a 60 page agreement like this - we will certainly be raising this with the Fair Work Commission."

Big W, however, claim that the new agreement actually "strengthens redundancy provisions for team members, with entitlements well above the National Employment Standards," and claims staff were briefed on the changes.

"All clause changes were clearly communicated to team members in print, online, and in face to face briefings held in stores with representatives from the Shop, Distributive and Allied Employees Association (SDA)," a spokesperson said.

"The majority of our store network is set to remain open and we're committed to doing the right thing for our team in impacted stores."

On Monday Big W announced 30 stores and two warehouses would close over the next three years.

Reports suggest Orange is one of the stores the retail giant is looking to close.