Qatar is suspending its role as a mediator in talks between Israel and Hamas after concluding that the two sides are no longer negotiating in good faith, two sources familiar with the situation tell CNN.

Qatar has suspended its key mediation efforts between Hamas and Israel, it said Saturday, after growing frustration with the lack of progress on a cease-fire deal for Gaza.

The Qatari Foreign Ministry announced it had stepped back from talks, saying it would resume once Israel and Hamas “show willingness and seriousness.”