James Cameron's "Avatar" Blu-ray discs and DVDs sold like hot cakes in the very first day at stores. Inspite of being available in the 2D format it recorded an overall disc sale of 4 million units, making it the year's top-selling film.

Blu-ray sales crossed a 1.5 million mark moving ahead of HD-The Dark Knight.

The figures stated by the retailers corroborated to amount an aggregate of 60% of their Blu-ray inventory, told a spokesman for distributor 20th Century Fox.

This release was posed with the significant 'Earth day'. Director, James Cameron and others who were linked to the same took part in a host of green-themed events as part of the movie's home-entertainment campaign.

Filmmakers expect to release a 3D version of the same and will come in Blu-ray Disc early next year. This move has been paused for the moment, as most of the homes are not equipped with Blu-ray players.