A last-minute order to stop coal mining was appealed by the largest opencast coal mine in the UK.
On Tuesday, an enforcement notice was scheduled to go into effect against the proprietor of Ffos-y-Fran in Merthyr Tydfil.
As the site's planning permission expired in September 2022, it would have given them 28 days to stop mining.
The Welsh government acknowledged the company's appeal on Wednesday morning.
A spokesman continued that further commentary would "jeopardize any future decision Welsh ministers may have to make on the matter" and that no further comments could be made.
An appeal "has been lodged with the Welsh ministers," the mining company Merthyr (South Wales) Ltd. confirmed, adding that it was unable to comment further while the appeal was still pending.
Chris Austin, 67, a local resident who lives close to the mine, has long advocated against it as a member of the United Valleys Action Group.
The mining company's decision to appeal the enforcement action, he said, "leaves us feeling extremely disappointed and frustrated.".
We once more request that a "stop order" be in place while this appeal is decided because, if accepted, the appeal could take a year or more to resolve. This makes perfect sense to us and most sane people, I believe.
There is no doubt that the mining company lacks the necessary planning consent to carry on mining coal at Ffos-y-Fran, so why are they still permitted to do so?
According to information on the Welsh government's website, after an appeal against an enforcement notice is submitted, a decision will typically be made "within 27 weeks, but it can take longer.".
It suggests that coal mining at the location could continue for another six months or longer.
The company requested an extension days before the 15-year-old planning permission to mine at Ffos-y-Fran ran out on September 6, 2022.
The planning committee of Merthyr council didn't discuss and reject the application until April 2023.
Between 7 September 2022 and 31 March 2023, 199,307 tonnes of coal were reportedly produced on the site as mining continued. .
The situation "sets a terrible precedent" and "brings the planning system into disrepute," according to attorneys working on behalf of the advocacy group Coal Action Network.
They claim that the local government and the Welsh government engaged in "maladministration," failing to address the situation more urgently and issuing a "stop notice," which may have been illegal.
To ensure "a safe cessation of coaling" at Ffos-y-Fran, Merthyr (South Wales) Ltd previously stated that it was in talks with the local government.
The council of Merthyr has also been asked to comment on the most recent development, but on Tuesday it stated that it took a "contrary legal view" from the attorneys for the campaigners.