Jaguar has announced updates to its XJ luxury saloon, which will take effect from the autumn.

The changes - which constitute a significant raft of upgrades - include some cosmetic tweaks to the car's exterior and interior design, new technology, an uprated engine and new trim levels.

The most obvious changes are to the outside of the car: they include a larger, more upright grille, full LED headlights (including daytime running lights), a new rear bumper and LED rear lights.

Inside the car, the focal point is a new infotainment system called InControl Touch Pro, which features an eight-inch touchscreen (featuring smartphone-like pinch-and-zoom capabilities) and is built around a quad-core Intel processor, 60GB solid-state drive and a next-generation Ethernet network to take advantage of advances in in-car connectivity.

The system also offers a Commute Mode that learns the owner's daily drive and can automatically offer alternative routes to avoid congestion, thanks to historical data and real-time traffic information.

There are also a number of apps that can be downloaded to smartphones and used to connect with the car or control functions such as remote locking.

In the back, an optional rear-seat entertainment system comprises a pair of 10.2-inch high-definition screens that fold away when not in use, which can connect to digital TV, and smartphones and tablets.

There are also numerous new driver assistance systems to improve safety, including All-Surface Progress Control (ASPC) that helps drivers pull away smoothly on low-friction surfaces; traffic sign recognition; a new queue assist function for the adaptive cruise control system; closing vehicle sensing; semi-autonomous park assist; and radar sensors for reversing that detect vehicles approaching and warn the driver.

Under the bonnet, the 3.0-litre V6 diesel now produces 296bhp and benefits from reduced CO2 emissions (down to 149g/km).

Also new are Autobiography and R-Sport trim levels: the former, for long wheelbase models only, includes a range of features to make the car more luxurious; while, as the name suggests, the latter emphasises sportier aspects of the XJ with a front splitter, rear spoiler, mesh grille and sports seats.

The revised XJ - which is manufactured at Jaguar Land Rover's Castle Bromwich Plant - will be priced from £58,690 on the road.