HAVANA — The commander of Colombia’s biggest rebel movement said Sunday its fighters will permanently cease hostilities with the government beginning Monday, as a result of their peace accord ending one of the world’s longest-running conflicts.

Rodrigo Londono, leader of the Revolutionary Armed Forces of Colombia, made the announcement in Havana, where the two sides negotiated for four years before announcing the peace deal Wednesday.

“Never again will parents be burying their sons and daughters killed in the war,” said Londono, who also known as Timoshenko. “All rivalries and grudges will remain in the past.”

Colombian President Juan Manuel Santos announced Friday that his military would cease attacks on the FARC beginning Monday.

Colombia is expected to hold a national referendum Oct. 2 to approve the deal for ending a half-century of political violence that has claimed more than 220,000 lives and driven more than 5 million people from their homes