Thousands of workers employed at a gold mine in northern Greece owned by Canada's Eldorado Gold protested in Athens Thursday over a government decision to revoke the company's licence.

Eldorado Gold's gold mine project in Skouries and a processing plant currently under development were used by the former Greek administration as evidence of that its pro-business policies were working.

But on Feb. 27 the Vancouver-based company received notice from the newly elected government that its licence was revoked.

Prime Minister Alexis Tsipras's government said it wanted to examine whether the mine and processing plant, currently under construction, was in line with town planning and environment regulations.  

An estimated 4,000 miners and other workers wearing vests and helmets marched to the ministry responsible for environment and development in Athens Thursday in support of the mine.

In the face of Greece's high levels of unemployment, the workers are worried they may lose their jobs. They waved flags which read "Yes to mines, yes to growth."

"We will not negotiate our right for employment, for dignity," representatives of the workers said in a statement.

Controversial project

A rival protest against the mine is scheduled for this evening.

The project in Skouries has been divisive from the start, with communities and environmentalists arguing it threatened the forest of Halkidiki and water quality in a natural area.

Eldorado Gold has invested $450 million in two Greek gold mines since 2012 and planned to invest another $700 million by 2017 in two more mines and a processing plant.

"We remain committed to the responsible development of our asset base in Greece and announced earlier this year that we plan to invest $310 million US on the development of Skouries and Olympias in 2015, which will generate additional jobs for the Greek people and taxes for the Greek government," Eldorado CEO Paul Wright said in a statement in February after the licence was revoked.

"However, the recent decision of the Ministry of Energy - if not reversed in a timely manner - may force Eldorado to reconsider its investment plans for Greece," he added.

Eldorado said it did not believe the action was legal as it has already passed an environmental review process.

With files from Reuters