SCANDAL-HIT car giant Volkswagen is facing legal action from hundreds of Scots owners 'duped' into buying vehicles they believed were low emission.

One leading law firm has said it is pursuing a mass litigation against VW after being inundated with calls on the back of the test-rigging revelations.

The action is said to be potentially one of Scotland's biggest ever legal cases.

Thompsons Solicitors said it estimated as many as 100,000 car owners in Scotland could be affected by the diesel emissions scandal.

It comes after VW pulled 4000 new vehicles from its UK showrooms and just days after the German car giant revealed that more than 1.1million of its vehicles already owned in the UK were affected.

The company said this week that within its various brands the number includes 508,276 Volkswagens, 393,450 Audis, 76,773 Seats, 131,569 Skodas and 79,838 commercial vehicles.

Meanwhile, Westminster said yesterday that motorists would not be forced to pay more in car tax even if their vehicles are found to be fitted with illegal software to cheat emissions tests.

The amount of vehicle excise duty, commonly known as car tax, depends on a vehicle's CO2 emissions.

AA president Edmund King described the clarification on car tax as "common sense".

VW has admitted that they used sophisticated software to cheat on emission tests, which allowed them to claim the cars had better green credentials than was actually the case.

Patrick McGuire, the Thompsons partner in charge of mass litigation, said: "Since news of this scandal first emerged we have taken hundreds of calls from concerned and in many cases furious VW and Audi owners.

"My firm has had to set up a special unit simply to field the number of calls and begin work on the legal case against VW.

"We will be pursuing them under consumer protection laws designed to protect the public for fraudulent practice. I would expect very sizeable settlements for those car owners affected."

Thompsons said it had taken taken from 254 VW and Audi owners and expected that number to rise considerably in the weeks ahead.

It said it had also set up a special dedicated hotline number for people who may be affected, predicting it will be a much bigger case than other mass litigation cases it has been involved, including the PiP breast implant scandal and metal on metal hip replacement.

Mr McGuire added. "It's the size of the fraud perpetrated by VW that is truly shocking. Potentially almost 100,000 car owners in Scotland could be affected. These are people who paid good money to buy a car they thought was good for the environment.

"Indeed many paid more for a car like this because they thought it was the right thing to do. Now they find they have been defrauded with the resale value of their vehicle gravely affected."

Meanwhile, the UK Government has launched an investigation to re-test cars to compare their laboratory results with real-world driving emissions

The Department for Transport said its inquiry will involve cars and testing facilities that are not provided by the motor industry.

UK Transport Secretary Patrick McLoughlin said: "The Government expects VW to support owners of these vehicles already purchased in the UK and we are playing our part by ensuring no-one will end up with higher tax costs as a result of this scandal.

"We are... starting our testing programme to get to the bottom of what the situation is for, VW cars in the UK, and understand the wider implications for other car types to give all consumers certainty.

"I have been pressing for action at an EU-level to improve emissions tests and will continue to do so. I have also called for a Europe-wide investigation into the use of defeat devices, in parallel to the work we are doing in the UK."