The P-F-A-I have described as 'deeply insulting' a plan for a 300 thousand euro fund to assist League of Ireland clubs with wage problems.
The Union have criticised the F-A-I for proposing they pay half of the scheme, without consulting them.
It follows the recent crises over unpaid wages at Bray Wanderers and Limerick.
Meanwhile, Celtic have one foot in the third qualifying round of the Champions League.
Two goals from Odsonne Edouard helped Brendan Rodgers' men beat Rosenborg 3-1 at Parkhead last night.
The sides will meet again in Norway next week, with the losers facing Cork City in the Europa League.
Stephen Kenny wants his Dundalk side to take their domestic form into Europe this evening.
The Lilywhites haven't tasted defeat since early May.
The Cypriots of A-E-K Larnaca visit Oriel Park this evening in the first leg of their Europa League second qualifying round tie.
