Fletcher Building has disputed First Union over claims over how its approximately 10,000 New Zealand staff are being treated during the month-long lockdown.
The union called for immediate Government intervention, saying one of the country's major employers and a big Government wage subsidy benefactor had misled workers.
Jared Abbott, union secretary for transport, logistics and manufacturing, said some staff had been misled over their eligibility for urgent financial assistance.
He also said Fletcher had "used and abused a national crisis to reduce the employment conditions of its workers, and was redistributing funds from the company into a welfare pool of its own to apply on a discretionary basis to its lower-paid workers while simultaneously refusing to top up their salaries beyond an arbitrary cap of their own invention".
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The company was running a welfare fund to help its lower-paid workers yet claimed it could not pay 80 per cent of their salaries. Fletcher was being allowed to set the standard for employment relations "and we should all be very worried by that", Abbott said.
But a Fletcher spokesman said the union had misrepresented the situation with "significant inaccuracies which we refute".
Fletcher employees were not being misled into losing rights as the union claimed and although "we engaged in a compressed consultation process, our employees were fully informed of the details of the bridging pay programme that they were agreeing to".
Fletcher had continued to engage with the few employees who had not joined the scheme, he said.
"We laid out a 12-week programme in line with the Government wage subsidy to provide our people certainty to allow them to plan ahead. As we work through the lockdown period and restart process, as we are able to bring our people safely back to work, they will return to their normal hours and pay even if it is with the 12-week period," the Fletcher spokesman said.
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More than 95 per cent of employees had already signed up for the bridging pay programme.
The small number of employees who had not agreed to the pay programme could be paid the Government subsidy for the period or use annual or long service leave, he said.
If redundancy was picked "we are open to discussing and it would be paid on their contracted entitlements".
The full Government wage subsidy had been passed on to employees, the spokesman said.
"No one will fall below the Government wage subsidy amounts during this period unless they already earn less than this amount. The subsidy amounts are $585.80 gross for anyone working more than 20 hours per week, and $350 gross for anyone working fewer than 20 hours per week."
If an employee's normal pay was less than the wage subsidy, they would get their normal pay during the 12-week subsidy period.
The Employee Welfare Fund was a private trust, independent of Fletcher Building and grants were made to employees and their families for serious medical events or financial hardship, the spokesman said.
"Fletcher Building has put additional funds into the fund for support to be provided to those of our people who need it. No Government subsidy money is going into the fund," he said.