Employment Minister Eric Abetz's comment that the sacking of waterside workers by text message may have been an "appropriate" form of communication in the context of a relevant industrial agreement has outraged unions and the ALP who accused him of raising the spectre of the 1998 Patricks dispute.

Hutchison Ports Australia sacked 97 workers in Sydney and Brisbane overnight on Thursday by text message and email.

Let go via text message: Former Hutchison worker Leyre Diaz. Credit:Peter Rae

When asked on Friday about the method of sacking, Senator Abetz said he was not aware of the circumstances.

"I don't know what the culture is in that particular workplace about communication between employee and employers – and if the culture is that employees can text message the boss and they in fact expect the boss to text message them, then that might be an appropriate methodology. I'm not going to comment on it, other than given whatever the culture might be you want employees and employers to treat each other with respect and due consideration," Mr Abetz said.