The retailer has also introduced an Online Egg Tracker to its own brand Natures Nest range, allowing customers to trace their egg back to the farm where it was laid. Eggs in this range are stamped with their own individual code before leaving the farm.

The code can then be entered on the Egg Tracker web site so shoppers can learn about the farm on which it was produced.

The introduction of 100 per cent British free-range eggs this week comes nine months earlier than Morrisons had previously targeted and will enable millions of laying hens to become free-range two years before the EU-wide ban on battery cages comes into force.

Jamie Winter, Trading Manager, said: "We sell over 10 million eggs each week, so our move to 100 per cent British free range will really make a difference to the welfare of laying hens and will enable more customers to buy free-range each week."

Morrisons work towards achieving 100 per cent British free-range own-label eggs, was recognised in December 2009 when it was named Egg Retailer of the Year by the British Free Range Egg Producers Association (BFREPA). The Award recognises the efforts and contribution made in encouraging consumers to opt for a free-range option when shopping for eggs.