<sod >Opec will reduce production by 1.2 million barrels a day to a ceiling of 32.5 million a day in "major step forward and a historic agreement".< eod>< sod > Opec will reduce production by about 4.5 per cent or about 1.2 million barrels to a ceiling of 32.5 million a day in "major step forward and a historic agreement", the oil producing cartel announced from its headquarters in Vienna on Wednesday.< eod>