Labour is looking to bring more "balance" to industrial bargaining.
Labour's finance spokesman Grant Robertson would not be drawn on the question of a move to industry-wide negotiation for pay, telling Q&A on Sunday "announcements will be made before the election in this area".
"What I can say is we want to strengthen the right to collective bargaining."
He said in the last nine years the rights of workers to bargain had decreased and wages had not kept up.
"We're the Labour Party ... we're about making sure that people get a fair deal in the workplace. We've always been that way."
He said, "I think the time's come to rebalance".
Labour leader Andrew Little is a former boss of the union now known as E tu.