On sale now priced from £21,495, the new Optima is initially offered in three trims, with GT and GT-Line versions to be added later in 2016.

Just one engine is offered: an upgraded EU6 version of Kia's 1.7-litre CRDi turbodiesel engine, now paired with either a six-speed manual or a new seven-speed (7DCT) dual-clutch auto transmission. This offers improved power of 139bhp – up 5bhp – and increased torque of 251lb.ft, up 11lb.ft and now starting from 1,750rpm.

With the Idle Stop & Go (ISG) engine stop/start system as standard, CO2 emissions of manual models are 14% lower at 110g/km, while fuel economy improves to 67.3mpg. Equipped with the new 7DCT dual-clutch auto gearbox, which replaces the previous six-speed torque converter unit, the Optima brings a 25% improvement in emissions to 116g/km, while fuel economy is now 64.2mpg.

A plug-in hybrid (PHEV) Optima will be added later in 2016 while a hybrid model is also being considered for right-hand drive markets. Kia has also said that the SPORTSPACE concept from the 2015 Geneva Motor Show hints at an estate version to come.

There are initially three trim levels – badged 2, 3 and 4 – which replace the previous 1-3 trims. Kia said the change is due to “the significant level of standard equipment which now comes with the vehicle, equivalent to competitor mid-grades” and also aligns the Optima with its other premium models, such as the Sorento and Sportage. It also means Kia can look to introducing a 1 grade in the future “should demand rise”.

The entry-level grade 2 version is manual only, grade 3 offers both transmissions while grade 4 comes with the DCT transmission only.

The 2 specification offers a 7.0-inch satellite navigation system with European mapping and a reversing camera, steering wheel-mounted controls, dual automatic air con, cruise control with a speed limiter, electrically heated folding mirrors and 17-inch alloys.

Grade 3 upgrades the navigation screen to 8.0 inches, has an eight-way power-adjustable driver's seat with four-way electronic lumbar adjustment, heated front seats and xenon dual projection headlights. It also brings 18-inch alloy wheels and an upgraded sound system as standard amongst other features.

Grade 4 adds in equipment including wireless mobile phone charger, 360-degree Around View Monitor, Smart Park Assist System, Blind Spot Detection with Rear Cross Traffic Alert and Lane Keep Assist, Adaptive Smart Cruise Control and black leather upholstery.

Prices start at £21,495 for the ‘2’ grade with 6-speed manual– up from £19,995 for the previous entry-level model – and rise to £28,895 for the range-topping ‘4’ specification with the DCT transmission.