Protestors smeared with black paint demonstrated Saturday against plans for petrol firm Repsol to drill for oil off the Canary Islands, which they say threatens tourism and wildlife.
About 100 young demonstrators with black handprints on their faces and shirts protested outside the national environment ministry in Madrid at midday, and further demos were planned on Tenerife and the other islands later Saturday.
"No tar on our beaches!" they yelled. "No to petroleum, yes to renewables!"
Environmental activists and the local government say Madrid's approval for Spanish firm Repsol to explore for oil off the Atlantic archipelago, one of the regions that make up Spain, threatens its vital tourism industry and rare marine life.
"The business is only going to benefit a multinational company" and will bring "absolutely no benefit" for the islands themselves, said a spokeswoman for the Madrid protestors, Noelia Sanchez.
"It affects the industry we live off, which is tourism, and is going to have disastrous social consequences," she added. "It is also going to mean disaster for the biodiversity of the islands."
Spain's deficit-laden government on March 16 approved oil exploration about 70 kilometres (40 miles) off the islands of Fuerteventura and Lanzarote, near the maritime border with Morocco.
Repsol, exploring the area in a consortium with Australia's Woodside Petroleum Ltd. and RWE AG of Germany, has said it hopes to begin drilling within two years.
It must first submit an environmental impact report to the government.
The regional government of the Canaries, Spain's second most popular tourism destination after Catalonia, has mounted a legal challenge against the project.
Greenpeace warned: "Deepwater operations are inherently dangerous and pose enormous risks of spills, fires and pollution as demonstrated by the collapse of the BP platform in the Gulf of Mexico less than two years ago."