IT started with a pub. Or at least it was at The Grenadier in Belgravia, London, where petrochemicals billionaire Sir Jim Radcliffe told friends over a pint that he was going to build a "proper 4x4".

Not only that, he settled on his favourite pub's name with its British overtones for this new creation by his company, Ineos.

It is still several months away from launch, but this spiritual successor to the original Land Rover Defender - Sir Jim owns the very first production Defender to be made - is now at an advanced stage in the pre-production process.

Tens of thousands of testing miles in some of the most challenging of climates and surfaces across the globe have now been completed and the final version of the Grenadier is more or less in the can.

Two engines are being offered both excellent six-cylinder three-litre BMW units. The petrol version will suit those who opt for power, while the diesel alternative will offer more torque.

The diesel engine is expected to be the bigger seller because a round two-thirds of Grenadier buyers will be business users and need the increased torque.

I was among one of several groups of UK motoring journalists given a taste of the Grenadier's off-road capability through woodland but also a brief feel for the car's measured road manners and - despite its weightiness impressive acceleration.

Of course, the Grenadier came through its off-road test with flying colours. It wasn't even noticeably uncomfortable. Sitting in a rear passenger seat, the auto transmission felt smooth and gear change were barely perceptible. It was even roomy back there, too.

Sir Jim pulled together experience and expertise across the board to create his vision. Apart from the BMW engines, there are transmissions from ZF and axles from tractor makers Carraro, and a big chunk of the development work has been done by Magna Steyr, who make the G-Class for Mercedes-Benz.

Assembly will take place in France, and the key phrase for the finished product is Keep It Simple. There's a ladder-frame chassis, three differential locks and a mechanical transfer box. If you want air suspension, then look elsewhere.

Inspiration has come from tractors, helicopters, boats and the like, but chief designer Toby Ecuyer was determined that the Grenadier should be honest and uncomplicated.

That's not to say that you won't find a host of creature comforts such as a 12.3-inch touchscreen on the centre stack, but big buttons and dials abound for those who might need to operate functions with a gloved hand.

Look up to the roof and you will find a host of buttons to deal with off-road situations, while on the floor are drainage holes so the rubberised surfaces can be hosed down.

The exterior is in a classic boxy style, breeds apart from the new Defender. There's a lovely touch at the back, where you will find not only a large side-hinged door but also a small side door for throwing in your shopping or kit bag.

Initially there will be two versions of the Grenadier, with only a limited choice in specification but plenty of scope to accessorise. The two-seat utility wagon is aimed at the commercial market, while the five-seat station wagon is perceived as more of a lifestyle choice.

Ineos is striking agreements with retail and aftersales partners around the world to establish up to 200 sales and service points by next summer, including 23 UK dealerships.

Reservations are now open, but this is only the start of the Grenadier story. A pick-up version will follow and a hydrogen fuel cell concept will begin testing by the end of 2022.

AT A GLANCE

Ineos Grenadier

Price: Expected to be around £48,000

Choice: Two-seat commercial or five-seat station wagon

Engines: BMW straight-six twin-turbo petrol (285 PS) and diesel (249 PS)

Transmission: Eight-speed automatic driving all four wheels

Towing capacity: 3.5 tonnes

Dimensions: 4,927 long / 1930mm wide / 2,033mm high

Performance, economy and CO2 emission figures not available

RATINGS

Performance: ****

Economy: N/A

Ride/Handling: ****

Space/Practicality: *****

Equipment: *****

Security/Safety: ****

Value For Money: ****

OVERALL: ****