The Bradford-based grocer has told the OFT that its prices would fall to the benefit of the consumer and promised that suppliers would not suffer as a result.
Morrisons said the merger would create a strong fourth force in UK food retailing to rival Tesco and Sainsbury in the south and Asda in the north and Scotland.
Executive chairman Sir Ken Morrison said: “We strongly believe that four national food retailers is better for competition than three. Morrisons and Safeway have little overlap.
“Any other combination would be bad news for customers who would face the risk of less choice and higher prices.”