The retailer also went some way to ease investor fears by announcing the appointment of Richard Pennycook as group finance director.
The trading statement said that total group like-for-like sales including fuel in the first 15 weeks of the current financial year had increased 5.4%.
Sales in the 108 converted Safeway stores excluding fuel were also up 12.5% from last year, with a 21.3% increase in customer numbers.
Like-for-like sales in the core Morrisons estate were also up 1.9% including petrol.
However, the statement concluded that Morrisons was unable to forecast profit levels for the year, mainly due to the Safeway acquisition.
Despite this, Morrisons said that the future looked promising with all Safeway stores expected to be converted to the Morrisons format by November. Morrisons stores were also holding their own, the statement said.
Pennycook will join Morrisons on October 1 and is currently group finance director for motoring and vehicle management company RAC.
He has also held senior management positions at HP Bulmer, Welcome Break, Laura Ashley, JD Weatherspoon and Allders.