Brazilian petroleum workers announced Wednesday that they would continue with a three-day-old strike at refineries across the nation after failing to reach agreement with the Petrobras state petroleum firm regarding wage hikes. The Petroleum Workers Federation (FUP) is demanding an increase of 13.2 per cent - a 5-per-cent increase after inflation. After a meeting Wednesday between FUP leaders and Petrobras officials, the government-owned firm said that it could not offer an increase of more than 7.81 per cent to refinery workers. Union leaders said that Petrobras will make a new offer on Friday in an effort to end the strike, affecting refineries in six Brazilian states. Workers are closing down refineries on alternate days. Workers at Duque de Caxias refinery in Rio de Janeiro returned to work after voting to end the protest Wednesday.