Barcelona’s world famous Sagrada Família will finally be finished by 2026, the architect in charge has vowed… nearly 150 years after work began.

That will make it ready in time for the centenary of the death of architect Antoni Gaudí, who famously joked that his client, God, was in no hurry to see it finished.

Since then 65 per cent of the work has been completed and now, with new masonry techniques speeding up the work, builders say the Almighty will only have to wait another 13 years to see its final spires and main façade.

‘If we continue at the pace we are now we will make it,’ said Jordi Fauli, the architect currently in charge of the project, as the foundation funding the building released a video imagining how the finished building will look.

Combining helicopter footage with computer animation, theYouTubeclip shows La Sagrada Família’s final stages take shape before your eyes.

Its grand spires shoot up in succession, with its central cupola rising into view. The Glory facade, which Gaudi envisioned as the church’s main entrance, appears to materialise from nothing.

While often referred to as a cathedral, and originally intended as such, La Sagrada Família was consecrated in November 2010 as a basilica by Pope Benedict XVI.

Cathedrals are the official seats of archbishops, but a basilica is a large and important church that has been given special ceremonial rights by the Pope.

But is it what he wanted: Critics warn that its final design will have little in common with Gaudí’s original vision

La Sagrada Família attracts around 3million visitors a year, whose entrance fees pay for most of the €25million a year cost of continuing its construction, with gifts from private donors making up the rest.

Construction began in 1882, with Gaudí’s involvement commencing the following year when he took over the project and radically transformed it’s design with his distinctive Gothic and curvilinear Art Nouveau style.

Problems have long dogged work on Barcelona’s second cathedral, with Gaudí neck-deep in the project when he was killed in 1926 when he was run over by a tram.

The architect’s body was not identified for several days after the impoverished 74-year-old was mistaken for a tramp. He lived long enough only to see a quarter of his masterwork completed.

Gaudí’s plans for the vast basilica, with its numerous towering spires, where then destroyed by anarchists opposed to the Catholic church during the Spanish Civil War. Much of its design since has been based largely on guesswork.

Packed with symbolism, La Sagrada Familia will eventually have 18 spires – one for every evangelist, one for every apostle and two, towering above the rest, representing the Virgin Mary and Jesus.

Critics have warned that its final design will have little in common with Gaudí’s original vision, a failing that the architect may not have had much trouble with.

He once said: ‘There is no reason to regret that I cannot finish the church. I will grow old but others will come after me.

‘What must always be conserved is the spirit of the work, but its life has to depend on the generations it is handed down to and with whom it lives and is incarnated.’