International Airlines Group, which owns British Airways and Iberia, lost (EURO)923 million ($1.2 billion) last year on restructuring costs and writedowns on the value of its Spanish unit.

The net loss announced Thursday compares with a profit of (EURO)412 million the year before.

Chief Executive Willie Walsh says Iberia must adapt to survive, a point he underscored by saying it must stem losses and permanently adjust its cost base.

He added that three months of negotiations with Iberia's trade unions had failed to produce an agreement on a restructuring plan. IAG has started a formal process that will eliminate about 3,800 jobs. IAG had given unions until Jan. 31 to reach agreement on the job cuts.