A rebel of Colombia's Marxist National Liberation Army (ELN) shows his armband while posing for a photograph, in the northwestern jungles, Colombia August 31, 2017. REUTERS/Federico Rios

BOGOTA (Reuters) - Colombia’s leftist ELN rebels said on Sunday they are willing to extend a ceasefire set to expire next month if there is sufficient progress at peace talks with the government.

The National Liberation Army (ELN) and the government have been in public peace talks in Quito for 10 months, after a long exploratory phase of negotiations, in a bid to end more than 53 years of war.

The group’s first-ever ceasefire began in October and is set to expire Jan. 9. It is being supervised by the Catholic Church and the United Nations.

“We are willing to agree a new ceasefire once we have jointly evaluated at the negotiating table the progress, confidence and results of the current one,” the group said in an open letter to the U.N. posted on the ELN’s Twitter account.

The ELN added that it would also assess the government’s willingness to overcome hurdles at the talks.

The 2,000-strong ELN, which has regularly bombed oil infrastructure and taken hostages, has continued kidnapping despite the ceasefire. An indigenous leader in Choco province died in October after being detained by the group.