Apple's CEO Tim Cook said in the Monday's three million new iPad sales announcement that the company had "practically sold out" of iPad minis, and further investigation has revealed that the 16GB models of the 7.9in iPad have sold out across the majority of Apple Retail Stores, while limited stock remains of other models.

The London Covent Garden Apple Store has sold out of all black models of iPad mini, and has some 32GB and 64GB versions left in stock, while the Regent Street Store only has limited black 32GB and 64GB models left, Apple representatives told us.

A poll carried out by Brian White and his team from Topeka Capital Markets on Apple Retail Stores in the US found that 60 per cent have sold out of all models of the iPad mini. Every store in the poll had completely sold out of 16GB models of the iPad mini.

The poll also found that, of the stores that had iPad mini stock remaining, 90 per cent had sold out of the 32GB black and slate model, and 76 per cent had sold out of the 32GB white and silver model.

The 64GB iPad mini is more widely available, with just 14 per cent of the stores with remaining stock sold out of the black 64GB model, and 10 per cent sold out of the 64GB white model.

An exit survey conducted as part of the research showed that those who purchased a 16GB iPad mini were more likely to opt for the white and silver model, while those buying iPad minis with larger capacities were more likely to choose black and slate.

Interestingly, White's survey found that 48 per cent of respondents had never owned a tablet before purchasing the iPad mini, indicating that Apple's new smaller iPad is appealing to a new audience.

Many customers who pre-ordered iPad minis from Apple's online store have found that Apple has pushed back the delivery date of their new device. "Demand for iPad mini exceeded the initial supply and while many of the pre-orders have been shipped to customers, some are scheduled to be shipped later this month," said Cook.

See also:

Apple loses tablet market share to Android iPad mini cases, covers & accessories iPad mini teardown 43 per cent gross profit margin for Apple iPad mini vs iPad 4 benchmark tests iPad mini vs iPad 3: Display comparison iPad mini beats Nexus and iPad 3 in drop test iPad mini display: testing books, comics, movies and games Video: UK iPad mini launch, lacklustre? iPad mini unboxing iPad 4 review Apple iPad mini review