Big John is the largest triceratops ever discovered on planet Earth.

       After the dinosaur's discovery in 2015 in the United States, it is now being assembled in an exhibition gallery in Paris to go on public display on September 16.

       But his show in the French capital would only last until it goes under the hammer for auction the following month.

       The 66-million-year-old dinosaur is estimated to fetch more than €1.2 million when the gavel bangs.

       Auctioneer at Drouot auction house, Alexandre Giquello, explains there's already a great deal of interest in the piece.

       "Usually buyers manifest a bit later, shortly before the auction, but here we have already noted a lot of interest," he said.

       Each part of its body considered a work of art in itself, has been painstakingly assembled to give shape to the prehistoric animal. His eight-metre long skeleton is more than 60 per cent complete.

       "On the top of being the biggest specimen in size, it is also very well preserved, up to 60 per cent of the skeleton which is incredible. Usually, we just find the skull of the Triceratops in collections," said Iacopo Briano, a fossil sales expert.

       Big John will be auctioned in Paris on 21 October at H？tel Drouot.