A labour expert says the recent spike in industrial action can't be blamed on the Government.

More and more groups are joining the picket line, with nurses, midwives, teachers, court staff and bus drivers among those calling for higher pay.

Victoria University academic Stephen Blumenfeld told Mike Hosking the strikes are part of an ongoing cycle.

"A number of collective agreements have come up for renegotiation in the past few months, causing a jump in bargaining activity."

LISTEN ABOVE AS STEPHEN BLUMENFELD SPEAKS TO MIKE HOSKING