The retailer, which said pre-tax profits rose to £406 million for the year to 3 February, added that it was considering alternative routes to import goods if its usual supply lines were delayed after Britain leaves the European Union.
"We have seen a very small amount of customers buying in," said chief executive David Potts. He added that the group saw a much more "challenging autumn as consumers were more cautious in more uncertain times".
The firm has increased stocks of “cupboard fillers” such as tins of soup and beans, following in the footsteps of rivals Tesco and Marks & Spencer.
Mr Potts said the group's turnaround was "well on track" and added that it responded quickly to the shift in consumer sentiment in the autumn as Brexit uncertainty took its toll, resulting in a successful end to 2018.
The chain saw like-for-like retail sales growth slow to 0.6% in the final three months, down from 1.3 per cent in the third quarter.
But like-for-like sales overall rose 3.8% in the fourth quarter thanks to a 3.2% contribution from the wholesale division, which includes tie-ups with McColl's and Amazon.