By Julia Symmes Cobb and Luis Jaime Acosta
BOGOTA, Nov 24 (Reuters) - Colombian President Juan Manuel Santos and former FARC rebel leader Rodrigo Londono each promised on Friday their continued backing to a peace deal they signed a year ago, despite slow progress on parts of the accord.
Both men spoke at an event to mark the anniversary of the final deal between Santos's government and the group then known as the Revolutionary Armed Forces of Colombia (FARC), which ended a 52-year war that killed more than 220,000 people.
The FARC, now a political party, have criticized the government for allowing some changes to the deal following a court ruling on a transitional justice law that will create tribunals to try rebel leaders for war crimes.
The deal remains deeply unpopular with many Colombians, who balk at the ten congressional seats guaranteed to the FARC through 2026 and want convicted rebels to serve time in traditional jails, rather than complete alternative sentences like land mine removal.
The government, for its part, says the accord has saved thousands of lives and will allow the country to focus on fighting crime gangs and growing the economy.
"I know the FARC have complaints and worries," Santos said in a speech at the anniversary event. "But have no doubt - we will continue to comply with the accord."
"Building peace is the biggest, the most important, the most valuable challenge that any country could have," he added. "Because of that I invite you, from the bottom of my heart, for you, for us, for our children, to keep advancing."
Londono, best known by his nom de guerre Timochenko, said the rebels had kept their word, handing over thousands of weapons to the United Nations and converting into a political party, for which they kept their initials.
"We are a serious party and we won't step back on any of the agreed terms. We are sure millions of Colombians who dream of an end to the conflict are with us, will fight for political solutions and understand that peace is achievable," Londono said.
Londono and Santos were also set to meet privately on Friday.
Santos has called on the country's lower house to pass legislation to approve the justice tribunals before the end of the month, when special provisions to speed debate expire.
The law has already been approved by the Senate and the constitutional court.
Two former Colombian presidents will back a joint right-wing ticket in elections next year, focusing their platform on objections to the peace deal.
(Reporting by Julia Symmes Cobb and Luis Jaime Acosta; Editing by Alistair Bell)
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