A decision is expected about whether work to build a new nuclear power station on Anglesey will be halted.
Japanese media has reported that Hitachi will suspend construction of its £20bn Wylfa Newydd plant – with the board due to meet on Thursday.
Wales’ Economy Secretary Ken Skates said he expected an announcement to be made during the morning.
Anglesey council said if the project was paused it would be a “tremendous blow” to the north Wales economy.
Mr Skates said he hoped that the plant would not be scrapped entirely.
“If it is paused then work must begin immediately across governments and with local government and with the business community in ensuring that there are job opportunities in the short term whilst we find a new investor for the project,” he said.
About 9,000 workers had been expected to be involved in building two nuclear reactors on the island, which are due to be operational by the mid 2020s.
But speculation has been rife that Hitachi will suspend work on Wylfa – a project of its Horizon division – or scrap it due to potential increases in construction costs.
Energy is not currently devolved to the Welsh Government but Mr Skates said an emergency economic ambitions board meeting will take place on Monday to discuss what job opportunities could be offered to people in the region.
He said it would also consider what additional support would be needed for the North Wales Growth Deal, which has been based on the premise that Wylfa Newydd would go ahead.
“Partners in north Wales have requested £170m for the growth deal and UK government, in spite of this comprehensive ask and programme of projects, offered £120m,” he said.
“My view is that sum, if Hitachi do pause the project, should be significantly increased.”
The plant would aim to have a generating capacity of 2900MW of electricity by the mid 2020s – enough power for about five million homes – and a 60-year operational life.
Dr Edward Jones, who teaches economics at Bangor University and advises the North Wales Growth Bid, previously said he doubted Hitachi will walk away from the project after already investing about £2bn.
He said the company’s £20bn investment in the plant is 20 times larger than the size of Anglesey’s economy, which has a GVA (Gross Value Added) of £1bn, and is also bigger than the entire north Wales economy, which has a GVA of £13.6bn.
Dylan Williams, Anglesey council’s head of regulation and economic development, said good jobs on the island were important.
“The recession hit Anglesey very hard and we saw several large employers leave the island,” he said.
“This led to an increase in outmigration and commuting elsewhere for work.”
He added that there was “no doubt” that if the Wylfa Newydd project was suspended it would “signal a tremendous blow, not only for the Anglesey economy, but also for north Wales and Wales as a whole”.
The UK government said it was in talks with Hitachi about Wylfa.
A spokesperson for the Department for Business, Energy and Industrial Strategy said: “Negotiations with Hitachi on agreeing a deal that provides value for money for consumers and taxpayers on the Wylfa project are ongoing.
“They are commercially sensitive and we do not comment on speculation.”