United Nations Secretary-General Ban Ki-moon has appointed UN envoy Jean Arnault of France to head the organization's political mission in Colombia.

UN deputy spokesman Farhan Haq announced Arnault's appointment on Wednesday. The political mission will monitor and verify a future peace deal between the Colombian government and the Revolutionary Armed Forces of Colombia, the country's biggest rebel group.

On Jan. 19, both the government and the FARC requested the UN Security Council to establish a mission for the monitoring of a ceasefire. A political mission was authorized on Jan. 25 in a resolution co-sponsored by all 15 members. This decision was an unusual event in the council, where opinions are often at odds.

Arnault's Role

Arnault is leading the UN's preparations for the mission's deployment in Colombia. He is also working closely with the negotiating groups from the Colombian government and the FARC on a sub-commission dealing, which aims to end the most longstanding armed conflict in Latin America.

Prior to Arnault's duty as secretary-general in Colombia, he was on a high-level independent panel reviewing UN peace operations, which included UN missions in Afghanistan, Burundi, Georgia and Guatemala.

President Santos Refuses to Sign a Bad Peace Deal

Colombian President Juan Manuel Santos said on Wednesday that he will not sign a peace agreement, which is due on March 23, unless a satisfactory deal has been agreed upon. He noted that his administration is willing to extend the negotiations if necessary.

"After all this effort, all this time, if we haven't reached a good deal by the 23rd, I'll propose to the other side to create another deadline," said Santos, adding that discussions are in their final stages, per Euro News. "I will not sign a bad deal to meet a deadline."

Santos' statement serves as his acknowledgement that the deadline may not be met. Other officials and the FARC have also doubted that a peace deal will be finalized on schedule.

Colombia and the FARC have been negotiating a peace deal since late 2012 to end more than 50 years of armed conflict. Partial agreements have been reached on transitional justice, land reform, guerilla members' involvement in politics, combating illegal drug trade, removing land mines and efforts to search for missing people.

One of the FARC's most pressing concerns is their safety once they lay down their arms.

Though peace talks with the FARC have been making progress, the same cannot be said for the National Liberation Army, Colombia's second-largest leftist group. The ELN attacked a military brigade in Arauca in February, prompting Santos to order a military crackdown against the rebels.