Peace talks between Colombia's government and its largest rebel group will begin next month in a bid to end Latin America's last and longest-running armed conflict, the two sides said.
The first such negotiations in a decade on ending nearly 50 years of fighting will begin in Oslo in the first half of October before moving to Havana, Colombian President Juan Manuel Santos said.
The talks "will be measured in months, not years," he added.
However, during the negotiations the army will keep up military operations against the guerrillas, known as the Revolutionary Armed Forces of Colombia, or FARC, and there will be no demilitarized zone set up, as was the case during the last failed talks in 2002, the president said in an address to the nation.
Santos said these points feature in an agenda agreed with the rebels in preliminary talks held in Havana over the past six months. "Military operations will continue with the same or even greater intensity," he said.
Guerrilla leader Rodrigo Londono, also known as "Timochenko," confirmed the opening of talks next month, in a recorded message released by the rebel delegation in Havana.
"We have the sincere hope that the government will not repeat past scenarios," the FARC leader said.
Mauricio Jaramillo, the leader of the rebel delegation in Havana, said the talks would represent "part of the difficult but necessary road to building stable and lasting peace for Colombia."
The discussions next month will likely address issues such as distributing land to peasant farmers, rebels' links to drug trafficking and reincorporating guerrilla leaders into everyday life -- a sensitive point, as many of them have been convicted of crimes against humanity.
"It's a very realistic, very detailed agenda that attacks the roots of the conflict," said Leon Valencia, director of the Nuevo Arco Iris research center, adding he was struck by the "message of reconciliation" offered by the FARC.
Founded in 1964, the FARC are Colombia's oldest rebel group and draw their roots from anger among landless peasants in a country with a gaping divide between rich and poor.
The United States welcomed the news, with President Barack Obama congratulating Santos.
"The Santos administration has demonstrated an unwavering commitment to seeking a durable peace and ensuring a better life for all Colombians through its security and social inclusion policies," a White House statement said.
"The FARC should now take this opportunity to end its decades of terrorism and narcotics trafficking, and allow the Colombian people to continue building a democratic, prosperous, and just society," it added.
Support also poured in from host countries Cuba and Norway, and from Chile and Venezuela -- which have been designated as "accompanying parties" to the process.
The European Union said the talks provided a "unique window of opportunity" to deliver peace, and urged the FARC to show sincerity by halting attacks.
"The violence must end," EU foreign policy chief Catherine Ashton said.
Santos said Colombia now has a roadmap that could lead toward a definitive peace accord and he had seemingly conciliatory words for the guerrillas.
"We have worked diligently, and I must acknowledge the FARC also. So far, everything that has been agreed has been respected. If the FARC address the next phase with the same seriousness, we have good prospects," Santos said.
He asked Colombians to show "calm, patience and strength" over the prospect of continued attacks by the rebels, and "unity so that the dream of living in peace will at least become a reality."
But his predecessor and political mentor, Alvaro Uribe, who cracked down hard against the FARC, condemned the opening of peace talks without the rebels first laying down arms.
"This is very serious because it means beginning dialogue without the end of the terrorists' criminal activities," said Uribe, who ruled from 2002 to 2010.
The FARC have around 9,200 fighters, down by half over the past decade after a series of military defeats, and have been largely corralled in rural areas.
Colombia has seen peace talks come and go before, three times since the 1980s. The government broke off negotiations last time around in 2002 after concluding that a vast demilitarized zone it had created for the rebels was used by them to regroup and rebuild.
Colombia has another, smaller rebel group called the National Liberation Army, which boasts around 2,500 fighters.