The Colombian government and the Revolutionary Armed Forces of Colombia, or FARC, have called on the United Nations to monitor a ceasefire even before they have signed an agreement on one.
The government and the rebels also asked the UN to oversee the process by which the guerrilla group would hand over its weapons after the formal end of hostilities.
The announcement, made on Tuesday, represents another major step towards ending the hemisphere's longest conflict.
"We have decided to ask the UN Security Council to immediately start to set up this political mission with unarmed observers for a period of 12 months that can be extended," they said in a joint communique.
The two parties have been negotiating an end to their conflict in Havana, Cuba, since November 2012.
With agreements already reached on tackling unequal land distribution, the rebels leaving the drug trade, and justice for victims of the long and bloody conflict, the talks now appear to be in the home stretch.
The only major hurdle remaining on the agenda is an "End of Conflict" deal, due to lay out how to implement what has been agreed, and how to definitively end hostilities.
"Today we have demonstrated the seriousness with which we are proceeding along the difficult path of leaving war behind," chief government negotiator Humberto de la Calle said during the announcement.
Tuesday's announcement received blanket coverage in Colombian media, where every new sign of agreement is seen as a welcome step towards a peace deal that has often faced skepticism.
Both sides announced a final accord would be reached by March 23 this year, when they signed a deal on transitional justice in September last year. That deadline now looks optimistic now, but an agreement is widely expected in 2016.
Though a formal stop to the fighting is still being negotiated, violence between the two sides has wound down to a de-facto ceasefire, according to local conflict-monitoring NGO CERAC.
Since the FARC took up arms against the government in 1964, at least 220,000 people have been killed and 6 million displaced, mostly civilians. State-aligned paramilitaries and drug cartels have contributed to the violence, with atrocities committed by all sides.
Speaking at a General Assembly meeting earlier this month, UN General Secretary Ban Ki-Moon stated that bringing peace to Colombia in 2016 is a priority for the organization.
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