BOGOTA, Colombia — One of the most prominent rebels from Colombia’s long conflict has joined his country’s reconciliation effort even though he is locked up in a maximum-security prison in Colorado with little immediate prospect of being able to return home, where thousands of other former combatants will earn pardons for similar war crimes.

Two Colombian officials said diplomats met with Ricardo Palmera at the U.S. government’s highest-security prison last week and he agreed to cooperate with a key component of the peace plan: special peace tribunals set up to seek justice for millions of victims of Colombia’s half-century conflict.

In the diplomats’ presence, he signed a document agreeing to testify to judicial officials about any war crimes he might have committed. The officials, who weren’t present at the meeting, spoke on condition of anonymity because they were not authorized to discuss the politically sensitive case.

The Revolutionary Armed Forces of Colombia have for years pushed for the U.S. to release Palmera, better known by his nom de guerre Simon Trinidad, as part of American efforts to support last year’s peace deal.

President Juan Manuel Santos also has urged Palmera’s repatriation, but U.S. officials have shown no sign of releasing him. Palmera, 67, is serving a 60-year sentence for conspiracy in the FARC’s capture of three American defense contractors who were held captive for more than five years a decade ago.

Hundreds of one-time rebels accused or convicted of serious war crimes in Colombia have been released from jail after signing identical pledges. Under terms of the peace deal, rebels, members of the military and civilian backers of illegal armed groups will be spared jail time if they confess their involvement in human rights abuses and work on social projects compensating their victims.

It’s not clear if any statement by Palmera about his actions in Colombia could affect his legal standing in the United States.

Born into a wealthy cattle-ranching family and the son of a senator, Palmera was an unusual recruit for the peasant-based FARC, and was seen as more of an ideologist than a combat leader.

His extradition and conviction in the U.S have long been held up by leftists who see him as a scapegoat and a symbol of what they consider to be heavy-handed U.S. meddling in Colombia’s conflict. When peace talks began in Cuba in 2012, the rebel group named him one of its five chief negotiators, using an empty seat and life-size cutout to draw attention to his imprisonment.

Palmera was extradited to the U.S. in 2004 and convicted of conspiracy to kidnap the three Americans. He was sentenced to the maximum 60 years, though he was not convicted of more serious charges of actual hostage-taking and terrorism as well as drug-trafficking. The Americans were rescued in 2008.

The diplomats from the Colombian Embassy in Washington and consulate in San Francisco who met with Palmera were accompanied by Sen. Ivan Cepeda, a trusted conduit of both the FARC and Santos government who visited the former rebel on four previous occasions. Also in attendance was Imelda Daza, a leftist politician who in the 1980s joined with Palmera in the Patriotic Union movement, a FARC-allied civilian movement that saw thousands of its members killed following a previous peace effort.

As part of behind-the-scenes lobbying, Palmera’s normally severe conditions of confinement were recently eased and he is now allowed limited contact with a few fellow prisoners. But he still faces special security restrictions like many of the other 400-plus inmates at the “Supermax” penitentiary in Florence, Colorado, among them Boston Marathon bomber Dzhokhar Tsarnaev and some al-Qaida operatives. They are kept in their cells as much as 23 hours a day and are normally allowed to meet only with their lawyers and family.

The Obama administration, a strong supporter of Colombia’s peace process, long rejected freeing Palmera. And there has been no indication that the Trump administration, which has blamed a record jump in cocaine production in Colombia partly on the peace deal, would be any softer.

Mark Burton, Palmera’s Denver-based lawyer, said his client’s eventual return to Colombia through a presidential pardon or some sort of prisoner exchange would help heal wounds.

With the FARC now disarmed, the argument for barring contact with the former guerrilla fighters is less compelling, he said.

“Colombia’s government, society and courts clearly want to hear from him. The U.S. government should respect that,” said Burton, who was not present at the prison. “Ideally they should send him home, but in the meantime he should be allowed to participate more actively in the reconciliation process.”


Joshua Goodman on Twitter: https://twitter.com/apjoshgoodman