Britain's biggest ever warship, the HMS Queen Elizabeth, has been officially accepted into the Royal Navy at a ceremony hailed a “major milestone” for the country’s armed forces.
The £3.1bn warship is the biggest ever built by the UK at 280 metres long and weighing 65,000 tonnes.
The Queen, Princess Anne and Defence Secretary Gavin Williamson today witnessed the vessel being accepted into the Royal Navy.
Captain Jerry Kyd described the commissioning ceremony, held at the ship's home base Portsmouth, as a "major milestone".
"Building aircraft carriers is not for the fainthearted. There are very few countries who can do this around the world," he said.
"So we should look at our British industry, our designers, all the skills, all the production companies around the country, the shipyards from Devon through to Fife, to the Royal Navy, who have come together to make this happen.
"We should be really proud as a country. This has been a national endeavour. It has just been fantastic - it is really a culmination of all our hard work."
Set to be the nation's future flagship, the aircraft carrier can be pressed into action for various tasks such as high intensity war fighting or providing humanitarian aid and disaster relief.
It will also serve as a floating military base for the F-35B stealth fighter jets that will launch from the deck of the vessel to undertake missions.
Cpt Kyd said hosting the Queen and having the monarch step on board for the commissioning ceremony was a "complete honour", adding that she would no doubt be "justly proud" of the sailors.
"I think this is the culmination of a number of years of real excitement," he said.
"The first sailing from Rosyth was only nine months ago, we have come a long way.
"The first entry into Portsmouth was in the summer and here we are today accepting the ship into Her Majesty's fleet formally.
"So, it is right at the top, it is the latest milestone, many more to come, but hugely exciting and a very proud day."
Speaking about what was next for the aircraft carrier after commissioning, Cpt Kyd said it was "all about operationalising the ship", getting her ready to "go out on the world stage".
"Next year is all about integrating the aircraft properly, helicopters at the beginning of the year and then we go to the United States to embark the F-35B, the new jet," he said.
"After that it is more training and we will prepare to go out on our first operational tour in a few years, so it is quite a racy programme.
"Putting together an aircraft carrier and all its facets and all its bits and pieces is quite a complicated business (but) one we are looking forward to.
"This (the commissioning) is a major milestone now, it is all systems go really."
During the ceremony the commissioning warrant was read and the Blue Ensign, which has been flying from the ship until its formal handover to the Royal Navy was replaced with the White Ensign.
The Queen was the first person to review a line-up of the royal guards.