A multimillion pound funding package to boost the economy in the north west cannot proceed without the return of devolved government, it has been confirmed.
The Londonderry and Strabane city deal was announced in May.
It would see the region receive £105m in government funding.
But Derry City and Strabane District Council chief executive John Kelpie has confirmed the release of the funding is dependent on a Stormont executive.
It comes after an earlier warning from the Northern Ireland secretary that devolved ministers were needed to approve the funding.
"It is a bit of a grey area as to when exactly the money will be signed off," Mr Kelpie told BBC Radio Foyle.
He said the council was able to proceed with agreeing heads of terms - an outline business case - with government departments and other stakeholders.
"At this moment in time the working assumption is that Stormont will match fund the UK government," he said.
"The point at which we are required to draw down money is some distance away yet.
"On that basis we are able to proceed in the absence of Stormont but clearly there will come a point when we will need that critical decision made."
The £105m Derry and Strabane district area city deal is to receive £50m to support innovation and grow the area's digital sector.
A further £55m has been allocated to an inclusive future fund for the region, the first of its kind in the UK.
The council anticipates the funding will be further boosted by the Northern Ireland Executive and additional financing from project partners and the private sector to bring the total investment to about £300m.
Mr Kelpie said it was hoped the first tranche of funding would be received in about 18 months to two years.
He said building work would then begin on the city deals major projects - including Ulster University's graduate medical school and centres of innovation and excellence in data analytics and robotics and automation. - between years four and six."