LONDON — Britain’s Royal Navy moved one step closer for its new aircraft carrier, the HMS Queen Elizabeth, to becoming operational, as the 65,000-ton warship sailed into its home port of Portsmouth for the first time on Aug. 16.

The warship entered the naval base, south of England, sooner than expected after the Royal Navy and the industry alliance that built the carrier changed the original plan and brought HMS Queen Elizabeth into Portsmouth midway through the sea trials now underway rather than when the tests were expected to be completed later this year.

Engineering work was originally planned to be undertaken at Rosyth Dockyard, Scotland, where the warship was built and then the sea trials got underway June 27, will now be conducted at the naval base ahead of the warship heading out for a second phase of trials.

About 12 days into the trials, the warship berthed at the deepwater port of Invergordon, Scotland, spending two weeks for a planned replenishment and refueling and the resolution of engineering issues.

The ship’s propulsion system was also checked by divers after the HMS Queen Elizabeth hit debris, possibly fishing nets, during the trials in the North Sea.

After resuming trials, the aircraft carrier returned to Invergordon earlier this month ahead of sailing to Portsmouth.

Speaking onboard the warship, Prime Minister Theresa May said, “Britain can be proud of this ship and what it represents. It sends a clear signal that as Britain forges a new, positive, confident role for ourselves on the world stage in the years ahead, we are determined to remain a fully engaged global power, working closely with our friends and allies around the world.”

U.K. Defence Secretary Sir Michael Fallon said the warship has made “good progress in sea trials and will now embark on the next phase of preparations that will see the return of Britain’s carrier strike ability.”

The British axed their remaining aircraft carriers in the 2010 strategic defence and security review to save money and have been taking a carrier strike holiday until the new warships are available.

Carrier operational skills have been kept alive largely by seconding U.K. personnel to the U.S. military.

When HMS Queen Elizabeth met with the USS George H.W. Bush and its carrier strike group during an exercise off the coast of Scotland recently, the Nimitz-class U.S. carrier had more than 60 Royal Navy sailors and Royal Marines onboard.

The war games saw the commander of the U.K. Carrier Strike Group, Commodore Andrew Betton, and his team’s direct jets, firepower and personnel across the task group for 10 days to hone skills for the U.K.’s own carrier strike capability.

HMS Queen Elizabeth is the first of two aircraft carriers being built for the Royal Navy in a £6.3 billion (U.S. $8 billion) program.

The second, HMS Prince of Wales, is close to completion and will be formally named next month.

The ships will not both be operated at once. The British do not have the manpower, money or aircraft to do that, but they will enable the Royal Navy to operate a single carrier continuously.

Both warships have been assembled by the Aircraft Carrier Alliance, with BAE Systems as a lead member. Large modules were built by six British shipyards and floated up to Rosyth for assembly.

The Royal Navy will operate the F-35B Lightning II short takeoff and vertical landing strike jets and Merlin airborne early warning helicopters from the warship.

The U.K. has 11 F-35B’s delivered so far. By the end of this year, all 14 jets so far ordered will be delivered. Flight trials from the carrier’s deck are on track to begin next year, with initial operational capability expected in 2020 and full capability three years later.

The British government said in its 2015 strategic defence and security review that it would buy at least 48 of the F-35B version of the strike jets and committed to eventually purchase 138 Lightening II, without specifying the types.

The F-35B will be operated by the Royal Navy and the Royal Air Force, but there have been hints the RAF could eventually be equipped with the F-35A version used by the U.S. Air Force.