The NFL announced that it will begin hiring and training replacement officials for possible use during the upcoming season.

The labor agreement between the league and the NFL Referees Association expired at the end of May and the two sides have been unable to agree to a new deal so far.

“In order to ensure that there is no disruption to NFL games this season, we will proceed immediately with the hiring and training of replacement officials,” the league said in a written statement.

Mike Arnold, lead negotiator for the referees association, said in a written statement that the league “never intended to work toward a fair agreement, even through mediation.”

There are no additional negotiating sessions currently scheduled, according to Arnold.