But international mediators rejected any substantive changes to the agreement.
There are now discussions whether an international mediator is a viable option, or whether elections will have to be held.
The plan, which was developed by international mediators, would go into effect only as part of an overall peace agreement.
Though the formal cease-fire has held for more than a year, international mediators have been unable to secure a peace agreement.
But international mediators have made no progress.
He is demanding the presence of an international mediator, a demand Belgrade has rejected.
He said urgent help from international mediators was "essential to peace and harmony in the region."
The Union is the international mediator that is accepted by both sides and whose presence does not raise controversies.
Last week, new cease-fires signed by the three parties encouraged international mediators to predict that an agreement was again within reach.
The next day international mediators met in Ukraine.