KIA has introduced a range of design improvements and new engines for the its Optima saloon and sportswagon models.

The new line up makes its debut at the Geneva Motor Show and will be on sale in the autumn.

The new Optima will be offered with two new powertrain options - Kia's all-new U3 1.6-litre CRDi diesel engine and a 1.6-litre T-GDi petrol power plant.

As well as refreshed exterior and interior design, the new Optima also features Kia's latest active safety and in-car connectivity technologies.

Kia's U3 diesel engine is designed to go beyond the stricter limits laid down by the Euro 6d TEMP emissions standard.

The new 1.6-litre engine replaces the earlier 1.7-litre CRDi and employs selective catalytic eduction active emissions control technology to reduce emissions. The new engine produces low carbon dioxide, particulate matter and NOx emissions. The powertrain develops 136bhp.

The Optima will also be available with Kia's 180bhp 1.6-litre T-GDi engine for the first time.

The lightweight turbocharged engine offers buyers a new petrol powertrain option between the naturally-aspirated 163bhp 2.0-litre engine and the 245bhp 2.0-litre T-GDi which powers the high-performance Optima GT and the new 180bhp 1.6-litre T-GDi is paired with Kia's seven-speed double-clutch transmission, which lets drivers change gear using steering wheel-mounted shift paddles.

The new Optima will be offered with Kia's latest seven or eight-inch touchscreen infotainment system, with navigation and Kia Connected Services powered by TomTom.

The system has Apple CarPlay and Android Auto to enable full smartphone integration and within the centre console is a wireless smartphone charger, allowing users to charge their smartphones on the move.

The infotainment system is linked to the Optima's new higher-resolution around view monitor which uses cameras at the front, rear and sides of the vehicle to provide the driver with a 360-degree view of their surroundings, making it easier to complete low-speed parking manoeuvres.

Michael Cole, chief operating officer of Kia Motors Europe, said: "The Optima enjoyed a record year of sales in Europe in 2017, with sales growing from 9,600 to more than 16,800 units last year.

"It is a key contributor to Kia's sustainable growth in Europe, and the Optima's sales momentum has been maintained through the introduction of new variants in 2017. These include Sportswagon and high-performance GT variants, and an ultra-low emissions Plug-in Hybrid powertrain."