"Whilst progress was made in mediated bargaining today between Port Otago workers represented by the Rail and Maritime Transport Union (RMTU) and the Maritime Union of New Zealand (MUNZ) and management a ban on overtime is still due to commence on Saturday," the two unions said in a joint statement.
"Discussions today did not result in sufficient progress for the unions to withdraw notice of the overtime ban, accordingly a complete and indefinite ban on overtime will begin this Saturday, however further mediated talks have been set down for next Wednesday 11 September," combined unions spokesperson John Kerr said.
Mr Kerr said the main sticking points remained as fatigue management and pay.
He said the overtime ban would have an immediate impact.
"Management are regularly dependent on workers to do 14 hour shifts in order to turn around ships. Worker availability for overtime will stop on Saturday. As the port gets busier in the build-up towards Christmas, this impact will be compounded.
We regret any inconvenience to port users or customers but we can no longer tolerate the real and meaningful health and safety risk to workers that fatigue represents," he said.
Port management was unavailable for immediate comment.
