Morrisons' share price was up 3.64 per cent at time of writing after the Bradford-based grocer reported a 2.9 per cent jump in like-for-like sales for the nine weeks to 1 January - its best sales for seven years.
This came as Kantar Worldpanel reported that supermarket sales lifted 1.8 per cent in the three months to January due to consumers spending nearly half a billion more on Christmas food than they did last year.
Tesco boosted its sales by 1.3 per cent, and the market rewarded it by boosting its share price by 4.4 per cent.
David Beadle of Moody's said:
Importantly, [Morrisons'] strong top-line performance is being achieved alongside ongoing cost savings. As such, the company are guiding for full year profits to be slightly ahead of previous market expectations.
The retailer said it expected its profit before tax to be ahead of consensus estimates, in the range of £330m to £340m.
Sainsbury's share price also benefited from Kantar's good news, rising 1.71 per cent, but Connor Campbell, financial analyst at Spreadex, said any enthusiasm for Sainsbury's was "tempered" because the supermarket is expected to reveal a drop in sales in its third-quarter trading update tomorrow.