Tesla chief executive Elon Musk on Friday called for fossil fuel-powered cars "to be tested at random," as German giant Volkswagen's worldwide pollution cheating scandal continues to reverberate around the globe.

"The obvious move is to pick cars at random and then test the emission in transit," said Musk at the unveiling of the US-based electrical carmaker's new plant in the Netherlands, the first in Europe.

Musk's comments come in the wake of revelations that Volkswagen equipped 11 million of its diesel cars worldwide with software that can switch off those pollution controls -- except when it detects the vehicle is undergoing official testing.

"Clearly emissions-testing needs to be more rigorous," Musk said after the shock discovery, which has thrown the focus on electrical cars and their environmental advantages.

The scandal broke a week ago when US officials publicly accused Volkswagen of cheating and launched a probe into the scam. The US has since been joined by a growing list of countries launching similar investigations.

"What we're seeing with diesel is that we've hit the limit," said Musk, whose new factory in Tilburg in the southern Netherlands will be able to pump out 450 high-end electrical cars a week.

He said he believed the German car giant "was under a lot of pressure to make improvements" in emission levels "and ran into a physical wall."

"After that, trickery is the only option," Musk said.

- 'Defeat devices' -

Musk's call comes as the US environmental regulator said Friday it will test all diesel car models for pollution "defeat devices."

The Environmental Protection Agency (EPA) said it would test cars under actual road conditions rather than just newly produced cars in the lab.

The German company is facing a potential $18 billion (16.1 billion euros) in EPA fines and has cost the job of chief executive Martin Winterkorn, who resigned Wednesday.

The cheating scandal also threatens to backfire on diesel, the fuel that powers most cars in Europe and is defended by manufacturers as a vital means to curb global warming.

France announced sample checks on diesel cars as soon as next week, after the European Union urged its 28 member states to investigate whether vehicles in their countries comply with European pollution rules.

Australia has also said it was seeking urgent clarification from the beleaguered Volkswagen on whether cars in the country had also been fitted with the device that fools pollution tests.

Late on Friday, officials in Switzerland said the country had suspended sales of VW models suspected with emission test-rigging technology.

The California-based Tesla's chief said all car manufacturers will eventually move to electrical vehicles, adding that he believed Volkswagen too should go "full tilt for sustainable-powered vehicles."

- Soaring share price -

Musk, who opened the doors to the giant factory which will assemble Tesla's Model S motor for distribution across the European market, said his own company hoped to turn a profit by 2020.

Tesla in August reported a quarterly loss of $184 million as the electric carmaker geared up for expansion.

But its shares are investor darlings on Wall Street, and its stock price has soared eightfold since the start of 2013, currently valuing the company at more than $30 billion.

Tesla plans to invest about $1.5 billion this year to expand production capacity, construct its huge "Gigafactory" in Nevada for batteries and expand its network of charging stations.

Said Musk: "We still have a lot of room to grow. We're (a car company) the size of a mouse (that gets) the press of an elephant."