Northern Ireland's largest school building project has been suspended after a bidder pulled out.
It followed delays caused by budget uncertainty over the next year and beyond, the Department of Education said.
Preparatory work surrounding the Strule Shared Education Campus (SSEC) at a former Army base in Omagh in Co Tyrone has been suspended, the department said.
Six schools are due to move to the site and use shared sports and other facilities.
A senior official said: "Earlier this week, the Department of Education received correspondence indicating a bidder's withdrawal from this tender process.
"As a matter of urgency, we are assessing the implications for the ongoing viability of the procurement of this contract.
"As a result, the decision has been taken to suspend this procurement process as we take stock of the situation.
"This is a disappointing development; however, the department remains fully committed to delivering the educationally and strategically significant SSEC programme and we will work closely with our stakeholders, including the local construction industry, to mitigate any impact."
Northern Ireland Secretary Karen Bradley has come under pressure to pass a budget from Westminster following the collapse of Stormont powersharing.
Many public services are struggling to plan amid the financial uncertainty.
The official's letter was published by SDLP Assembly member Daniel McCrossan.
He said: "A further delay throws the viability of the entire project into doubt.
"This is a critical development for the north west. It should provide a boost for the construction industry, create new jobs and advance shared education in our communities.
"It's imperative that we do all we can to protect and advance the project."