Colombian President Juan Manuel Santos announced Friday that the historic peace deal ending almost half-century of conflict with FARC rebels will be formally signed on Sept. 26.

The Revolutionary Armed Forces of Colombia (FARC) — the country’s largest rebel group — and the government of Colombia had been engaged in a five-decade-long war that killed more than 220,000 and displaced millions, Reuters reported. The accord is the final result of about four years of extensive talks in Havana, Cuba with the ceasefire having begun Monday.

“Peace will be signed on September 26 in Cartagena,” Santos said, calling it “perhaps the most important announcement” of his life.

FARC leader Timoleon “Timochenko” Jimenez also corroborated the announcement by tweeting the date and location of the signing, calling it “the foundation for building #peace.”

FARC will hold its tenth and final conference as an armed group from Sept. 17-23, where the leadership of the rebel group will brief rebel commanders on the contents of the accord in the conference postponed from the original dates of Sept. 13-19.

According to the provisions of the deal, once the formal signing is complete, the rebel will have 180 days to relaunch itself as a political party after demobilizing and disarming themselves under the watchful eye of the United Nations. Previously, there had been speculation of the deal being signed at the U.N. headquarters in New York.

In a referendum to be held on Oct. 2, the citizens of the country will vote on — “Do you support the final accord to end the conflict and build a stable and lasting peace?”

Agence France Presse reported that according to a new poll out Friday, 59.5 percent are expected to vote “yes” in support of the agreement, almost double of those in disagreement. To ratify the deal, 13 percent of the voters need to be for the accord.