Cork GAA are seeking an urgent meeting with Cork City Council after they had a planning application for Páirc Uí Chaoimh turned down.
Earlier this year, Cork GAA had submitted plans for a new museum and visitor experience, as well as alterations to the Monahan Road entrance to the ground.
The main sticking point for local residents, however, was the plan to convert a green space into a car park.
Cork City Council rejected the proposals, to the "surprise and extreme disappointment" of Cork GAA.
In a statement, they said, "We submitted this planning application in good faith following extensive pre-planning consultations with Cork City Council, and had sought to engage positively and constructively in the process.
"As applicants, we were expecting a request for further information from the Planning Department, and would have fully engaged with that process as is standard practice in most applications of this size and scale.
"No such request was forthcoming."
Cork say "serious safety issues and infrastructural deficits" remain at the €96million stadium.
They add, "The outright refusal raises serious and immediate questions about the safety of the existing vehicular access to Páirc Uí Chaoimh via the pedestrianised Marina.
"Cork GAA has grave concerns about this ongoing situation.
"The issue of insufficient disabled parking in proximity to the stadium, which was highlighted prominently in the application, remains a critical deficit.
"The Board will continue to seek an appropriate resolution to the issues outlined, and will now consider all options.
"We will continue to seek to engage with residents groups and all interested parties in a meaningful way as we work to achieve the full potential of the stadium for all the people of Cork.
"The Board of Páirc Uí Chaoimh and Cork GAA will seek an urgent meeting with Cork City Council to discuss the refusal of the planning application."