RIO DE JANEIRO:  -- The fate of Argentina's largest oil company, YPF, was thrown into doubt on Thursday as reports that President Cristina Fernández de Kirchner was preparing to nationalize the company drew a warning from Spain that it would consider such a move a hostile action.

Colombia:

Colombia Reports:  YouTube reactivated the account of an exiled Colombian key witness in the "parapolitics" case against the country's former prosecutor general Thursday, three weeks after suspending the account.

CARTAGENA: Colombia -- The stereotype of Colombia -- violent, chaotic, backward -- seemed to be born out in recent days...  As President Obama arrived Friday in this coastal colonial gem, joining presidents and CEOs at the Summit of the Americas, he heard about another Colombia: prosperous, a magnet for investment, ever more urban and modern. It is the Colombia that attracted record levels of foreign investment and whose economy grew nearly 6 percent last year, that was awarded investment-grade status and can borrow more cheaply than some countries in Western Europe.

See Obama's Colombia visit itinerary.  Boz examines eight issues at the summit.

Colombia Reports: Former President Alvaro Uribe continued his denial of paramilitary ties in an interview with RCN Radio Friday. Uribe denied accusations that he helped found paramilitary groups during his 1995-1997 tenure as the governor of Antioquia, despite having openly acknowledged in the past that he supported CONVIVIR, a network of anti-guerrilla neighborhood watch groups formed in the 1990s.

Colombia Reports:  More than 60 indigenous communities are in danger of disappearing as they fall victim to hunger and the ongoing armed conflict, the president of National Indigenous Organization of Colombia (ONIC) said Thursday.

Reuters:  Mexican President Felipe Calderon met with his Cuban counterpart, Raul Castro, on Wednesday as the two sought to restore friendly relations and explore new trade opportunities after rocky times between their two countries. Calderon's office said the two men agreed on "the importance of the bilateral relationship, based on mutual respect, the observance of the norms of international law and the close friendships of the Cuban and Mexican peoples."

IPS:  MÁLAGA, Spain, Apr 12, 2012 - A group of former political prisoners from Cuba and their family members gathered in Madrid's Puerta del Sol square and in front of the foreign ministry Tuesday to protest the unexpected cut-off in aid from the government.

The Economist:  A popular student rebellion shows that, as Chileans become better off, they want the government to guarantee a fairer society. Politicians are struggling to respond.

Al Jazeera: Springfield, MA - Honduras now claims the dubious distinction of being the murder capital of the world as drug trafficking and gangs play an undeniable role in the violence plaguing the small central American country.

CARACAS - Russia's Gazprombak Latin America Ventures will operate two oil fields in northwestern Venezuela in a joint venture with Corporacion Venezolana del Petroleo, or CVP, the government said.