Talks began in October in Oslo, Norway and continued the following month in Havana. Norway and Cuba are acting as guarantors for the negotiations, with diplomats present at the table.
De la Calle said the talks will go on for 11 days, followed by a three-day break, before resuming again. Colombian President Juan Manuel Santos has said the negotiations must bear fruit by November or he will walk away.
Several past efforts at peace have failed, though there is growing optimism both sides want to find common ground.
The rebels have seen their numbers dwindle in recent years due to an aggressive government military campaign, funded in part by the United States, though they insist they are still a potent force. The FARC has been fighting the Colombian government since the 1960s.
Associated Press writer Anne-Marie Garcia contributed to this report.
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