In a statement released on their website on Sunday, the DBU slammed Spillerforeningen for ambushing them with a new set of demands after the national governing body had compromised and agreed to negotiate for a collective deal.
The DBU had initially demanded individual negotiations with each player involved in the senior men's team, women's team and under-21s.
But after the players made it clear they would not accept that process, DBU relented.
According to the DBU's communications manager Jakob Hoyer, however, that was not enough for Spillerforeningen.
"It's a very strange situation. We have always been open about DBU's economic problems and suddenly we are met by a requirement that Spillerforeningen want more money for the national teams," he said.
"It is completely unrealistic and seems far different the signals that have come from the national team players, who have said that the collective agreement was decisive - not salaries."
The failure to reach an agreement leaves Denmark's upcoming senior friendlies against the United States and France under threat, but Hoyer remains optimistic that DBU can convince the players to play those matches, even if it requires a temporary deal.
"We're focused on playing those games - we owe it to both our fans and our opponents," he said.
DBU and Spillerforeningen have been negotiating for over a month and want to reduce the national team's collective salary by 17 per cent after losing over 4.5 million Danish kroner (£430,100) over the past two years.
