By Belén Carreño
The project was granted preliminary approval in early 2013 but has since faced local opposition.
Berkeley later requested a trading halt on its shares, which fell nearly 29 percent in Australian trading hours on Tuesday, citing media articles about the Salamanca mine.
The company asked the Australian Securities Exchange to suspend trading until it released a statement on the Salamanca mine or until the opening of trade on Oct. 19, whichever came first, according to the letter sent to the regulator.
Berkeley said it had received no official notice from the Nuclear Safety Council nor any other government department regarding its plans to open the mine and had contacted the Spanish authorities to seek clarification.
It said it would make an announcement as soon as a response had been received.
Berkeley had said on Tuesday it was still confident it would obtain the last two major permits needed for the mine to start operating - a local building licence and an authorisation given by the government to handle radioactive waste - though it would also scale down its existing local corporate operations.
"The government will wait for the ongoing proceedings to go through but it will say no," a government source said on condition of anonymity.
Spain's energy and environment ministry declined to comment. The Nuclear Safety Council had no immediate comment.
A second source, directly involved in the proceedings, said Berkeley was "living in a parallel universe" when it said the mine would soon become a reality.
"The authorisation to build the mine is only possible when the nuclear authority has handed over its report, which is still a long way," said the source, adding he believed the mine would never see the light of day.
The nuclear authority is due soon to renew its board and the Socialists and junior parliamentary allies Podemos, who both oppose the project, will hold a majority in it.
A neighbouring mine run by public company ENUSA was previously in operation near the site in Retortillo in Salamanca province, but closed in 2000 after it failed to turn a profit.
Berkeley, which has a triple listing in Britain, Spain and Australia and operates no other projects, has insisted the planned mine can be profitable since conducting initial studies in 2007.
The price of uranium fell heavily following Japan's Fukushima nuclear disaster of 2011 and for years struggled to recover.
This year, however, investors hope for profits as prices have rallied, helped by London-listed investment vehicle Yellow Cake, which has been buying and storing the element.
Berkeley said the mine would run for 14 years, generating investment of over 250 million euros (220 million pounds) and more than 2,500 direct and indirect jobs in the region.
In a study presented to Australian investors, the firm said the mine is capable of generating strong, sustainable cash flow as a result of recovering demand and growing appetite for uranium ore coming from China.
(Reporting by Belen Carreno, additional reporting by Jose Elias Rodriguez in Madrid and Barbara Lewis in London; writing by Julien Toyer; editing by Dale Hudson and Louise Heavens)
By BelÃ©n CarreÃ±o