A stretch of coastline which is one of the most important sites in the UK for seabirds such as Arctic terns and Atlantic puffins has been declared a protected area.
The newly-designated Northumberland Marine Special Protected Area (SPA) stretches 12 miles from the coast into the North Sea and covers 400 square miles, Government conservation body Natural England said.
The area of coastline supports 200,000 seabirds which flock to the area to feed, nest and breed.
Many of the birds belong to rare species and the area is the most important site in the UK for Arctic, common and roseate terns, the second most important for sandwich terns and the third most important site for Atlantic puffins.
Designation of the SPA under the European Union Birds Directive builds on existing special protected areas covering seabird breeding sites at Coquet Island, Farne Islands, Lindisfarne and the Northumbria Coast.
It is intended to minimise disturbance to the birds' open water feeding areas and help protect the full range of habitats they seabirds rely on.
Natural England hailed the SPA designation a "major step forward", saying in the past it had been concerned that while the breeding ground of birds were being protected, their feeding ground were not.
They continued that they hoped to put in place similar protections right around the coast of the UK.
Andrew Sells, the body's chair, said the designation marked a "momentous day" for some of the UK's best-loved and most charismatic seabirds, many of which had suffered population declines in recent decades.
"These designations will protect vital feeding areas for seabirds along the English coast, creating safe havens to help the birds thrive for generations to come," he said.
However, activists have said the populations of seabirds have "nosedived" in recent years as climate change has altered the fish stocks that the birds rely on for food.
The only way to alter this decline they said, is to tackle global warming head-on.
Environment Minister Therese Coffey said: "We already have one of the strongest track records in the world when it comes to looking after our precious marine environment, and Thursday's designations will strengthen our blue-belt of protected areas while helping seabirds across the country thrive."
Chris Corrigan, director of RSPB England, said: "It is fantastic to see these special places being recognised and given the protection they so need and we hope to see more designations in the very near future.
"As the UK moves closer to leaving the EU, we urge the Government to continue to recognise the significance of protecting these sites, based on scientific evidence, and that they continue to protect and manage these sites to the same or even higher standards than those currently secured by European law for generations to come."
Natural England has also announced extensions to Hamford Water SPA in Essex and Morecambe Bay and Duddon Estuary SPA in Cumbria, adding an area bigger than 150,000 football pitches to the existing marine protected area network.