Energy Secretary Andrea Leadsom has demanded more information before deciding whether to give planning permission to a nuclear project on Anglesey.
Ms Leadsom had been due to give a decision on the Development Consent Order application to construct the £12bn Wylfa Newydd power station.
But she today deferred the decision for six months to obtain additional information on environmental and other impacts on Anglesey.
The project is currently in a state of limbo after it was suspended by Hitachi in January after they failed to reach a funding agreement with the UK Government.
The applicant and other stakeholders have to submit additional details before December 31.
A final decision is now expected by March 31 2020.
A BEIS spokesman said: "There are outstanding issues which mean that we are unable to reach a decision based on the information provided to us.
"The Secretary of State has therefore extended the deadline for deciding the application to allow further information in respect of environmental effects and other outstanding issues to be provided and considered.
"The applicant and other interested parties will be given until 31 Dec 2019 to respond to our request for further information. This will then be assessed, potentially including public consultation, and a final decision taken on or before 31 March 2020."
It had been hoped that securing planning for the site would give the scheme fresh impetus and help drive through a new deal to fund the scheme with alternative arrangements for new nuclear projects currently being studied.
Developer Horizon Nuclear Power is due to comment shortly.
