Hundreds of construction workers staged protests in Dublin and Galway this week, alleging that money belonging to them had been paid into Dutch bank accounts without their knowledge.
Gama Construction employs about 800 mainly Turkish workers in Ireland.
Gama denies the allegation and says workers have always had access to the accounts, held at a bank in Amsterdam. The company has been at the centre of controversy since February when Socialist TD Joe Higgins accused it in the Dáil of engaging in “immigrant worker exploitation of massive proportions”.
The workers have complained of hourly rates of pay of as little as €2 to €3.
Last week, Higgins revealed that the workers only found out about the affair when the company urged them to tell government inspectors that their wages has been paid into the Dutch accounts.
Gama now says it is issuing a letter in Turkish to the workers telling them how to access their accounts.
The SIPTU trade union denied that it had failed to respond to the matter at an earlier stage.
Last month, a Filipino woman was found to be earning just one Euro an hour - one seventh of the minimum wage - for the Irish Ferries company.