Colombia this week marks one year of talks to end Latin America's oldest insurgency, making substantial gains towards peace despite continued fighting between the government and leftist rebels.

The current negotiations between the Bogota government and rebels with the Revolutionary Armed Forces of Colombia began November 19, 2012 in Cuba.

Unlike in previous failed talks, Colombians -- who have endured nearly 50 years of conflict that has left thousands dead -- now believe peace actually might be attainable.

But the dialogue over the year has advanced in fits and starts. It was put on hold again on Sunday, when negotiators for the government and and the leftist FARC rebels, postponed the next round of talks planned for November 18.

"By common consent, it was decided to postpone the start of this round of talks, because they asked for more time to work on the issue of illegal drugs," a source close to the negotiations said.

The source added that there is as yet no "precise date" for a resumption of the talks.

Observers said coming elections also threaten to disrupt the negotiations, which nevertheless have registered more gains than any other efforts at negotiated peace.

So far the two sides have agreed on land reforms designed to narrow the gulf between destitute farmers and ultra-rich landowners -- the root cause of the war's eruption in the 1960s -- and agreed on letting the leftist FARC rebels take part in politics if a peace accord is in fact achieved.

"What we have just achieved has no precedent in peace processes in Colombia. It is the first time we have gone so far, and that is an effort worthy of praise and a very important step," said Sandra Borda, an expert in international relations at the University of the Andes in Bogota.

For all its gains, the process has been anything but a bed of roses.

The FARC did keep a pledge to observe a two-month unilateral truce as the talks got under way a year ago, but fighting has continued. And the government rules out any talk of a ceasefire until there is a final peace accord.

"Public opinion cannot tolerate the idea of the government stopping fighting," said Borda.

In the last talks, which lasted from 1999 to 2002, the government agreed to create a vast demilitarized zone for the FARC, but ultimately concluded that the rebels just used this concession to regroup and rearm, and it called off the talks.

This time around, President Juan Manuel Santos "learned the lessons of history," Borda said.

So far this year at least 61 soldiers and 75 guerrillas have died in combat, according to an AFP toll.

But that bloodshed has not apparently hindered the peace talks.

"There was never a red line established that could not be crossed and which would force us to suspend the dialogue," a government official told AFP.

'Hit the accelerator'

Christian Voelkel, the Colombia delegate for a conflict analysis think tank called Crisis Group, said "the foundations are very solid and the risk of a collapse still seems to be a very remote, given all that it would cost both the government and the FARC."

But the clock is ticking, and Santos recently asked the delegations to "hit the accelerator."

Three items on the negotiating agenda remain: drug trafficking -- a major source of funding for armed groups in Colombia -- reparations to war victims and getting the guerrillas to disarm.

Another pending issue for the government is future talks with another leftist rebel group, the National Liberation Army, or ELN.

Meanwhile, presidential elections are scheduled for May, and legislative voting will be held in March. Santos will probably run for another term, and many Colombians are wary of the peace process.

With the election campaign imminent, former president Alvaro Uribe, a former ally of Santos but now his most outspoken critic, accuses him of betraying the country by negotiating with what he terms terrorists.

Uribe is still very popular for his all-out fight against the FARC while in office, right before Santos. In eight years, he managed to slash the FARC to half its previous size, and now it numbers 8,000 fighters.

The former president, who will probably run for the Senate for his conservative party Democratic Center, might be in the crosshairs of the FARC. Recently the government said it had foiled a rebel plot to kill Uribe.

"The political and electoral dynamics could jeopardize the peace process. So we are at a crossroads: what happens in the next five months before the legislative elections will probably be decisive for the sustainability of the peace process," Voelkel told AFP.