Mending relations with a neighboring nation is one of the first challenges Juan Manuel Santos will face. Tensions between the two South American nations are high, as Venezuelan President Hugo Chavez sent troops to the border with Colombia last week, following a series of diplomatic dispute.
Ties between the two Andean neighbors were broken off in July, after the government of Colombia's outgoing President, Alvaro Uribe, accused Venezuelan leaders of harboring Colombian rebels in their country's territory.
Security has since been beefed up on both sides of the border.
Venezuelan President Hugo Chavez warned an attack was imminent.
But most analysts believe war between the two sides is very unlikely.
Saturday's swearing-in of new Colombian President Juan Manuel Santos is likely to calm the waters.
He has repeatedly said he's willing to mend ties with Venezuela.
Chavez also sent out an encouraging signal, dispatching his Foreign Minister to attend his incoming counterpart's inauguration ceremony.
The Venezuelan leader has also vowed to recover billions of dollars of trade lost due to bickering between the two governments.
Goodwill has been shown by the both sides.
But how to implement it remains a problem.
Santos has vowed to continue Uribe's crackdown on Colombian rebels, and this could once again impact the reeling relationship between the two countries.
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