Apple's rumoured 5.5-inch iPhone 6 will come with exclusive features including a 128GB storage option and a camera equipped with optical image stabilisation, it has been claimed.

Sources from China suggest that the larger handset will be available with either 32GB, 64GB or 128GB of on-board storage, Digital Spy reports citing MacRumours.

Previous leaks strongly suggest that the 5.5-inch phone will be announced alongside a smaller 4.7-inch iPhone 6, tipped to come with either 32GB or 64GB of storage.

Apple's iPhone line traditionally offers a 16GB option, but the latest report appears to indicate that the firm is doing away with this.

Photographs of both the 4.7-inch and 5.5-inch iPhone 6 models have previously leaked online, suggesting they will feature rounded edges.

Apple is expected to announce both devices alongside the iWatch this autumn.