Eldorado Gold says progress has been made with government over issue of permits as miners demonstrate in Athens

Greece’s biggest foreign investor has withdrawn its threat to pull out of the country in an apparent breakthrough over work permits as miners railing against the prospect of unemployment took en masse to the streets of Athens.

George Burns, chief executive of the Canadian mining company Eldorado Gold, said enough accommodation had been reached over the issue of outstanding licences to allow “constructive talks” with the government over its future in the country.

His announcement came as more than 1,000 miners, protesting against the prospect of possible job losses, descended on the capital, blockading the environment ministry before angrily marching on the Greek parliament.

Miners from mountain villages whose families have been working the gold and copper reserves for generations feared they would lose jobs if the row over long-delayed licences was not resolved. Most in the capital on Thursday had travelled overnight on coaches from northern Greece, where Eldorado operates two goldmines.

“We have come to Athens again to claim a right to our livelihood, a right to a wage,” Giorgos Hatzis, representing workers at one of the mines, told reporters. “We are not going to stop claiming the sacred right to work.”

Facebook Twitter Pinterest Miners outside the environment ministry in Athens. Photograph: Anadolu Agency/Getty Images

In echoes of a controversy in Romania, where the Canadian mining company Gabriel Resources has faced fierce opposition from local activists, Eldorado has confronted entrenched resistance over its operations from opponents citing environmental concerns.

The loudest criticism has come from leftists in the governing Syriza party. More than 2,000 jobs are on the line in an investment exceeding $3bn – by far the largest in a country where one in five are out of work.

Earlier this month the Vancouver-based firm gave the government until 22 September to issue the permits, saying it would suspend operations if the deadline wasn’t met.

After violent protests outside the environment ministry last week, licences were provided for a pre-existing underground mine at Olympias, on the Chalkidiki peninsula, but not for an open-pit mine at Skouries. Eldorado expects each mine to have a life of at least 25 years, and more than 500 miners work in Skouries alone.

With foreign investment key to cutting unemployment, the prime minister, Alexis Tsipras has exhorted his cabinet to facilitate endorsement of major state sell-offs, but sensitivities remain, with leading Syriza figures complaining that Eldorado is trying to cut corners.

Stergios Pitsiorlas, the deputy development and economy minister handling investments, told the Guardian that while Athens wanted the mining firm to stay “there are rules and everyone has to respect them”. Contractual obligations had to be kept, he said. Much of the controversy has centred on metal production techniques.

The Canadian company has agreed to enter an arbitration process to settle differences with Greek authorities including compliance with environmental regulations.

In a statement it insisted that the Skouries licence was not part of the process. “Upon receipt of the required Skouries permit and the Greek government being willing to engage with us in constructive discussions, the company will then be in a position to re-assess investment options in Greece,” it said.