Waitrose will convert to using free-range eggs in 100% of its own-label products from next month.

The supermarket chain has been working towards its 100% target for three years, having refused to sell fresh eggs from caged birds in any of its stores since 2001.

" Our switch to free-range egg as an ingredient demonstrates a long-term commitment to high-welfare values," said a spokeswoman.

Since Christmas, Waitrose has been targeting the final 5% of non free-range foods.

"Completion of this final phase is a major milestone for us," said Cheryl White, head of Waitrose food technology.