BMA has refused to rule out locking out striking workers from its Bowen Basin coal mines.
AAP reports the Construction, Forestry, Mining, and Energy Union says BMA is rumoured to be considering a lock-out, and BMA has refused to comment.
BMA said it's continuing to focus on reaching an agreement with the unions through negotiations.
The news comes as mining union delegates from BHP's operations yesterday gathered in Mackay to show solidarity for striking workers.
The Daily Mercury reports the CFMEU said the meeting was about sharing information on what was happening on BMA's mines.
Yesterday the CFMEU said it would not back down from its fight with BMA and it had not talked with the company since fresh strikes started last week.