The Melbourne CBD has been closed this morning as thousands of union supporters protest for a increase in minimum wage and job stability.

The protests, held in every capital, were an attempt to fix the "broken" industrial relations system says CFMEU  spokesperson Sean Reardon.

Minister for Jobs and Industrial Relations Kellie O Dwyer called the rallies a "glimpse of a bleak industrial relations future’ where unions have the ability to ‘break any laws they like."