The union representing Streets ice-cream factory workers will urge the public to boycott its products including Paddle Pop, Golden Gaytime and Magnum over the summer if the company terminates their agreement on pay and conditions.

The Australian Manufacturing Workers Union said it was planning to organise a boycott of Streets ice-creams including the icon Paddle Pop if multinational Unilever, which owns Streets, proceeded with its application in the Fair Work Commission to terminate the current enterprise agreement.

The boycott would be similar to the one imposed on beer giant Carlton and United Breweries products in 2016 during a long-running industrial dispute. The public supported the boycott on products including Carlton Draught, Carlton Dry, VB, Crown Lager and Pure Blonde.

AMWU secretary Steve Murphy said Streets workers in the Sydney suburb of Minto had raised serious concerns about the threat of a significant pay cut if their enterprise agreement was terminated and they were forced back onto the award safety net.

Mr Murphy said the difference between existing wages and those offered under the relevant award which would apply if the agreement was terminated, would amount to a 46 per cent pay cut. Unilever has said it needs to create more flexible working conditions and enhance the competitiveness and viability of the factory in the longer term.

When the AMWU recently asked how workers would cope with a big cut in pay, many said they would struggle with paying their mortgages and risked losing their homes.

Among the many text messages sent by Streets workers to the union was one that said: "How am I going to feed my family, pay my home loan that was granted based on my current wage, pay my bills, clothe my children?"

Another said: "I'll lose my entitlements that I've negotiated over 19 years."

One other said: "If my pay drops I'm worried I won't be able to pay for living expenses plus treatment my kids need as they have autism and need lots of therapy ... It's hard enough as it is now..."

Mr Murphy said the text messages revealed the "human impact of an industrial relations system that is rigged against working people".

"Imagine being the father of a child with autism who has to lie awake at night wondering how you will continue to care for them with a 46 per cent pay cut. Imagine the stress of not knowing how you will afford to pay your mortgage because you're going to lose nearly half your pay," Mr Murphy said.

"When big corporations like Streets and Unilever are allowed to unilaterally cut pay by 46 per cent, real workers and their families suffer.

"To add insult to injury, workers are being gagged from speaking out publicly under threat of the sack."

A spokesman for Unilever said the company gave Streets ice cream employees and the union an undertaking last week to preserve pay rates under the existing enterprise agreement until April 30 next year or earlier if a new agreement is reached.

"This commitment to employees would take immediate effect should the Fair Work Commission agree to terminate the existing enterprise agreement," the spokesman said.

"The undertaking was conveyed in person to employees in onsite briefings last week. It would come into effect in the event of a Fair Work Commission decision to terminate the existing enterprise agreement, a matter currently before it for consideration.

"The intent of Unilever's commitment is to provide our employees with a period of stability while discussions are ongoing to find a mutually agreeable solution to make the factory more viable and competitive in the long term."

Earlier this month, Unilever rejected the union's claim that the company would oversee a 46 per cent cut to employee wages as having "no basis in fact".

ACTU secretary Sally McManus accused Unilever of "industrial blackmail" after it applied to the Fair Work Commission to terminate the enterprise agreement.