"The Phil", as it's known in the city, was built in 1898 by architect Walter W Thomas during the "golden age" of pub building in the 19th century.

The venue, opposite the Liverpool Philharmonic Hall concert venue, is notable for its exuberant grand stone exterior and richly decorated interior.

John Lennon once complained that the worst thing about being in The Beatles was "not being able to have a pint in the Phil".

Band-mate Paul McCartney returned to the city where the band made their name and surprised drinkers with an impromptu show there in 2018.

The pub, Grade II listed since 1955, now joins other architectural gems such as Buckingham Palace and Chatsworth House after Historic England upgraded it to a top-ranking Grade I.

Duncan Wilson, chief executive of Historic England, called the Phil a remarkable survivor from the Victorian era. 

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The listing "will help maintain and preserve its outstanding interior fittings and exterior fabric for the future", he added

The pub's exterior boasts obelisk finials, tall chimney stacks, turrets and a balustraded balcony around the second floor.

Its art nouveau entrance gates are considered to be among the finest of their style in England.

Inside, ornate plasterwork, detailed stained glass, and mahogany fireplaces surround the horseshoe-shaped bar.

Landlord Eamonn Lavin said the new listing was a "real honor".

"We got people from all over the world -- Japan, America, France, everywhere, Europe -- and they all come in just to see the building and sample some of the beers and drink," he told AFP.

"So it's got real rich history as well. And Liverpool is a city that's quite interesting anyway. So, this is just the icing on the cake for tourists really."