The deal between the Colombian government and the country's leftist guerillas could help many nations address issues ranging from climate change to extreme poverty, President Juan Manuel Santos told the U.N. General Assembly on Tuesday.

The South American country's peace process and the resulting end to the longest armed conflict in the Western Hemisphere "could be used as a model for other armed conflicts across the planet," Santos said, acknowledging the talks had marked a "difficult but not impossible mission."

The president also addressed critics who said the deal would deny justice to thousands of victims since ex-fighters who cooperate with the government would be able to avoid prison time, Reuters reported.

"Is this the price we are paying in terms of sacrificing some justice? Is it a reasonable price to pay?" Santos wondered in an interview with the British newswire. "And the answer is: Of course it is, by far. Because the alternative is to continue 30 more years of war," the president insisted.

Bogotá and the leader of the Revolutionary Armed Forces of Colombia (FARC) had announced a breakthrough in the long-running negotiations last week as both sides agreed on a framework for investigating rights abuses, the Wall Street Journal reported.

The agreement stipulates that a newly created Tribunal for Peace -- made up of Colombian and international judges -- will consider legal cases against guerrillas and collect testimony and evidence to determine compensations. The body would also deliver sanctions in the case of serious crimes, such as mass killings.

While the deal has not been finalized, economists -- and Santos -- already estimated that a successful implementation could significantly boost Colombia's gross domestic product, according to CNBC .

"The impact on economic growth is going to be very positive," the president predicted at the United Nations. "There have been many calculations -- I would say on average, and I'm using a conservative estimate, the growth of the country could increase around 1.5 percent forever."

The Colombian leader promised that his nation's citizens would eventually vote on the final deal in a referendum, though he insisted that he was not legally required to take that step, the channel added.