Sony's Xperia Z4 smartphone may have been revealed in a series of "internal renders" which have surfaced online, Digital Spy said.

The images were created for in-house use at Sony and originated from a trusted source, according to French website Nowhereelse.

The 3D renders resemble previous leaked images of the Xperia Z4, which appears to sport a similar design to last year's Xperia Z3.

Subtle differences include the removal of a microSD slot beside the SIM tray and the addition of the waterproofed micro-USB found on the Xperia M4 Aqua.

Previous reports suggest that the Xperia Z4 will be powered by a Qualcomm Snapdragon 810 chipset, backed up by either 3GB or 4GB of RAM.

It is also expected to include a 5.2-inch display with either a full HD or Quad HD capabilities, while retaining the 20.7-megapixel camera of its predecessors.

A release date for the Sony Xperia Z4 is yet to be announced.