A Stormont department has been forced to relinquish seven controversial mining licences after what it terms an “oversight”.

The licences were awarded by the Department for the Economy (DfE) in May despite more than 2,000 objections.

They gave a provisional green light for international mining companies to begin prospecting across swathes of counties Armagh, Fermanagh, Tyrone and Derry.

But on Friday afternoon, DfE issued a brief statement saying the companies had agreed to relinquish the licences in the hope of undertaking a fresh 12-week consultation process.

The statement came as a group campaigning against the prospecting licences received correspondence from the Department of Finance’s top solicitor indicating that the licences were being surrendered in response to a legal challenge.

The Save Our Sperrins group had previously submitted a pre-action protocol letter setting out the grounds on which it planned to launch a court challenge.

According to DfE, public notices of the intention to grant the prospecting licences was passed to the Belfast Gazette but they were not published as required under legislation.

fFidelma O’Kane from Save Our Sperrins. PICTURE COLM LENAGHAN

The Belfast Gazette is a British government-run publication in which public notices are published, often to ensure legal compliance.

Save Our Sperrins spokesperson Fidelma O’Kane said the latest development was “representative of our executive’s failure to carry out its proper duty”.

“This botched process is just the latest in a series of questionable decisions made against the wishes of local people,” she said.

“While failure to publish these public notices is given as the reason for the licences being relinquished, we believe there are many reasons they should be stopped.”

Foyle MLA and SDLP economy spokesperson Sinéad McLaughlin said there was “significant public opposition and environmental concern” around mineral prospecting.

She said no further licenses should be granted until a comprehensive review of mineral licensing was completed.

“This is further evidence of the incompetence at the heart of our executive, alongside their say one thing and do another approach,” she said.

The Belfast Gazette has been approached for comment.

The Department for the Economy said it had been advised to readdress its “oversight” by seeking approval from the companies to relinquish the licences, “which has been agreed”.

DfE previously said it was “carrying out a comprehensive review of mineral licensing” but that existing law must be complied with in the meantime.