Havana, June 23 (RHC)-- UN Secretary General Ban Ki-moon has arrived in Havana to attend Thursday's signing of a historic ceasefire agreement between the Colombian government of President Juan Manuel Santos and the country's largest guerrilla group –the Revolutionary Armed Forces of Colombia-Peoples’ Army (FARC-EP).

The breakthrough deal, reached after nearly four years of negotiations, reportedly includes terms on an armistice, the handing over of weapons, and the security of insurgents who give up their arms.

The UN Secretary General’s presence in Havana is regarded as vital to the monitoring and verification of the agreements, particularly after the UN Security Council approved on January 25, 2015, resolution 2261, establishing a political mission of unarmed international observers to monitor and verify the Colombia peace process.

The UN chief arrived in Havana Wednesday evening, accompanied by Security Council President Francois Delattre.

Other world leaders who have already arrived to Havana to attend the signing of the landmark agreements include the President of the UN General Assembly Mogens Lykketoft and Salvadorian President Salvador Sánchez Cerén.

Thursday's ceremony will be presided over by Colombian President Juan Manuel Santos and FARC-EP Commander Timoleón Jiménez, together with Cuban President Raul Castro and Norwegian Foreign Minister Borge Brende, representing the guarantor countries. Chilean President Michelle Bachelet and her Venezuelan counterpart Nicolás Maduro will also attend, representing the group of countries that have accompanied the peace process.

The President of the Dominican Republic and current President of the Community of Latin American and Caribbean States (CELAC) Danilo Medina and the U.S. and European Union special envoys for the Colombia peace process will also attend.