Colombia, which borders Venezuela and has been flooded by people fleeing the economic and political strife
there, has refused to recognize the new legislature of President Nicolas Maduro but still hopes there will be a peaceful resolution.
"The Maduro regime has been shifting towards a dictatorship. I would consider that regime, today, a dictatorship," Santos told CNN's Christiane Amanpour
"A dictatorship in the middle of Latin America, in a country which is as important as Venezuela, is something very bad for everybody," he said.
But Santos rejected US President Donald Trump's comments about not ruling out a military option
"A military intervention will not be accepted by Colombia or by any other country in Latin America. This is not the way to go about this crisis."
Advice: Stay away from Twitter
Santos, who was awarded the Nobel Peace Prize for his pact with the FARC guerrillas
in Colombia, said behind-the-scenes talks were the best route to success, even in a situation as difficult as dealing with North Korea and its leader, Kim Jong Un.
"We think that Twitter is the worst way to manage a good diplomacy and I think that through diplomacy, through dialogue, almost any problem can be solved," he said on "Amanpour."
"If you start escalating in words then the possibility of escalating in real terms, in military terms, will become a closer possibility and that would be a terrible thing for the world," he said of the current US-North Korean tensions.
"My advice, and I think the advice of most of the world, is please insist through diplomatic channels, through dialogue. Because insulting each other from one side to the other and escalating the aggressiveness will only have a bad result."
Santos will welcome Pope Francis to Colombia this week
to celebrate the peace with FARC and a new truce with ELN guerrillas.
"He comes in the perfect moment to push us, in his own words, for the Colombian society to reconcile, to leave aside 53 years of war, of death, of violence and start working together to construct that peace. He comes in the perfect moment," Santos said of the pope's visit.
And he hoped war is truly over
for his nation.
"The guns are silent now. The guns of the FARC, by far the biggest group, are in the hands of the United Nations. They're going to be converted into three monuments of peace."