British retailer Waitrose pledged to source all its seafood from independently certified sources by the end of 2016, it announced Thursday.

The move builds on its responsible fish sourcing policy, which was launched 15 years ago. Waitrose also hopes the move will help ensure a  "longer-term guarantee of sustainability in the face of increasing global pressure on fish stocks."

“For us, this pledge feels like a natural evolution of our long-standing responsible fishing policy," Jeremy Langley, fish buyer at Waitrose said in a statement.