Council of Trade Unions president Helen Kelly says the organisation's relationship with the Government has broken down.
Ms Kelly released a letter on Monday that she sent to Prime Minister John Key last week outlining the council's concerns about proposed changes to the labour laws, including restricting union access to workplaces.
Her letter says Mr Key breached an undertaking given to the council that he would talk to them if union access were back on the agenda.
Ms Kelly says the council has given the Government a fair chance and taken part in events such as the job summit and the Holidays Act review.
From now on, she says the council will pick and choose what it participates in.