The new cost for the development of Casement Park has dropped to £270m, BBC News NI understands.
It follows the decision by the GAA to slightly modify the stadium design after plans to host some games of the Euro 2028 football tournament in the stadium were dropped.
Initial estimates suggested it would have cost more than £300m to complete the west Belfast ground to Uefa specifications.
Last month GAA president Jarlath Burns said the new design was “basic and modest” but would still cater for more than 30,000 fans.
At the time he said it was a “significantly smaller cost” as they had removed much of the “fit out”.
“We have managed to retain the number of people who will fit into it, while having it to a lower specification,” he said.
The GAA president refused to disclose the new cost of the stadium, which the BBC now understands to be £270m.
Mr Burns was speaking after a meeting with Communities Minister Gordon Lyons, which he described as positive at the time.
It has now emerged Mr Burns accused Lyons of “dragging his heels” on the project during the meeting.
He also challenged Lyons over his failure to attend any GAA matches.
One source said the talks at times were “fraught and tetchy”.
Lyons has attended a GAA event but not a match.
The minister has also insisted the Northern Ireland Executive will fulfil a previous financial pledge to support the Casement Park development.
It promised £62m while the Irish government has pledged more than £40m with the GAA offering a further £15m.
That leaves a shortfall of around £150m if the stadium is to be completed to the current price tag.
The GAA is now seeking a meeting with Secretary of State Hilary Benn to discuss the revised cost with a view to securing funding from the government.