The group’s aim is to speak with Volkswagen UK boss Paul Willis. Greenpeace and several doctors have set up a makeshift clinic to highlight concerns about the effect of diesel emissions, particularly nitrogen oxides (NOx).
Greenpeace has targeted Volkswagen in the wake of the Dieselgate emissions scandal, pinpointing it as the biggest seller of diesel-engined cars in the UK.
It also cites Volkswagen’s refusal to give up on diesel despite greater backlash across Europe as another reason for its criticism.
A Volkswagen spokesman said: "Paul Willis offered Greenpeace 18 months ago the opportunity to visit Wolfsburg in order to find out more about our future strategy. The letter has not been answered."
Rosie Rogers, clean air campaigner at Greenpeace, said: "Today's protest has taken a few months to plan. We are still waiting to hear if Paul Willis will come down to meet us today. We’re targeting Volkswagen because it is the biggest producer of diesel cars and puts 1 in 5 diesel cars on UK roads.
"If Volkswagen quit diesel, it would have a big impact on the air our kids breathe. And it would wave an enormous red flag to the entire industry that it’s time to stop diesel car production in its tracks. On top of this, Volkswagen owes angry consumers a real debt because of Dieselgate."
When asked if Greenpeace is planning any protests at non-automotive pollution sources, Rogers said: "There aren’t any plans for this at the moment, as air pollution that is harming people’s health in towns and cities is predominantly caused by diesel vehicles.
"Today, we’re hoping to get some face time with Paul Willis and speak to Volkswagen employees about the harm Volkswagen’s diesel plans will cause. But ultimately, we want Volkswagen to commit to end production of diesel cars and set a trajectory for 100% electric vehicles."
Volkswagen issued the following statement: "Volkswagen is aware of a protest at its Blakelands premises this morning. The safety of our employees is our principal concern and so the matter is now being handled by the police.
"The Volkswagen Group has launched the most comprehensive electrification initiative in the automotive industry with Roadmap E. This will bring an additional 80 new electric vehicles to the Volkswagen Group model range by 2025. Roadmap E brings a €20 billion investment to electric vehicle technology with the goal of 25% of Volkswagen Group vehicle production comprising electrified vehicles by 2025 and 50% by 2030."