BOGOTA  (AFP) – The Colombian senate’s approval Thursday of looser terms in peace talks sends a strong message to leftist guerillas who have been battling the government for half a century, experts said.

The constitutional reform proposed by President Juan Manuel Santos, which must still pass the House of Representatives and Constitutional Court, allows for the possibility of amnesty for demobilized guerillas.

It also sets out provisions to provide restitution to victims of the decades-long conflict and opens the door for former guerillas to gain political office so long as they did not perpetuate crimes against humanity.

“It is essentially a message to the guerillas — they’re saying here is a way to make peace,” Fernando Giraldo, a political science professor at the Javeriana University.

Colombian law currently imposes hefty prison terms on guerilla leaders accused of terrorism and bars them for life from political office. Amnesty is only offered for non-violent political crimes.

“It’s a law for peace,” said Ariel Avila of Corporacion Nuevo Arco Iris, a think-tank promoting peaceful resolutions to the Columbian conflict.

“It opens a door to dialogue and offers a legal grounding to support it.”

The approval does not signal that talks are imminent, cautioned Giraldo.

“Society needs a pathway to escape this interminable armed conflict, but peace is not around the corner,” he told AFP.

In public speeches this week Santos urged the military to attack guerillas with force and insisted that if a dialogue is opened “it will be on our conditions and under our controls.”

“This is an approach to guerillas in retreat. But we are 10 years into ‘democratic security’ (the policy of fierce combat against the guerillas) and the armed conflict is still there,” Giraldo said.

Columbia has been riled in a bloody internal conflict that has killed, injured and displaced hundreds of thousands of people over the past 50 years.

Two guerilla groups are active: the Revolutionary Armed Forces of Colombia (FARC), which was founded in 1964 and has an estimated 9,200 fighters, and the National Liberation Army (ELN), with another 2,500.

The last peace talks which resulted in the demobilization of some guerillas was the Movement of April 19 in 1990, which involved a general amnesty.

Since then, the FARC has held talks with the Colombian government in 1991-1992 and then again in 1999-2002, but without reaching any agreement.

“Most of the guerrilla leaders have been convicted in absentia, so the only thing they can offer is a stay of execution of sentence,” said Javier Ciurlizza, program director of the International Crisis Group’s center for Latin America conflict analysis.

“For middle and low ranking members the reform envisages the possibility of suspension of the judicial process and the principle of future opportunity in exchange for confessions,” Ciurlizza added.

FARC has offered to open a direct dialogue with Santos in order to end the conflict and earlier this year announced the cessation of kidnapping of civilians for ransoms as a gesture in that direction.

In April, the FARC released the last 10 policemen and soldiers who were kept captive for almost 14 years.