Pressure is mounting on Tourism Minister Arlene Foster to rubber-stamp an application to fund a new £2m building for the Free Derry Museum before time runs out this month.
The delay by the minister is jeopardising a cocktail of funding which is in place and ready to be released, according to the museum.
The application has already been approved by European funders but the Northern Ireland Tourist Board, has been waiting for Mrs Foster to sign off on the project since February.
Foyle MP Mark Durkan described her eight-month delay as an "unworthy and unnecessary difficulty", while John Kelly (right), whose brother Michael was killed on Bloody Sunday, said the project is almost out of time.
The Heritage Lottery Fund has approved £500,000 for the project and £300,000 has been agreed by the Department of Social Development.
However the lion's share of funding – £1.2m – was expected from Mrs Foster's Department of Enterprise, Trade and Investment (DETI).
The offer from the Lottery will expire at the end of the month, unless DETI's funding can be secured.
Mr Kelly, the education and outreach officer at the Free Derry Museum, said: "We have been waiting for eight months now on Arlene Foster's signature.
"When the time runs out, which is very, very soon, we will not have the money to do this.
"This is an educational project. It educates people as to what happened on Bloody Sunday and there are people coming here from all over the world."
Mr Durkan said he was very concerned that a delay in confirming the funding could jeopardise such the entire project.
"Other funding lines for the Free Derry Museum could be lost in the absence of the necessary confirmation from DETI," he said.
However, a spokeswoman for DETI said: "As the project promoters have already been advised, the project is currently being considered.
"All projects are assessed as part of the approvals process and it is not appropriate to indicate where in the approvals process any projects sits."
Minister Foster declined a request for an interview.
"The project is dead in the water if we cannot get them [DETI] to release the letter of offer for £1.2m."
Conal McFeely, chairman of the Bloody Sunday Trust, which runs the Free Derry Museum