Unions representing FairPoint Communications workers in northern New England say they view its potential $1.5 billion sale to an Illinois-based broadband and business communications company with cautious optimism.

Union leaders said Monday they’re looking closely at Mattoon-based Consolidated Communications’ finances, technical capacity and history of labor relations and the regulatory requirements for the sale.

The agreement and proposed merger have been approved by the boards of directors at Consolidated and at Charlotte, North Carolina-based FairPoint. The deal’s expected to close by mid-2017.

FairPoint’s largest network is in northern New England, where FairPoint said last month it was laying off at least 110 workers because of a downturn in its traditional telephone service. About 35 of those jobs would come out of Maine.

The statement came from the International Brotherhood of Electrical Workers System and Communications Workers of America, representing more than 1,500 workers.