Argentina has been playing a double-headed role in attempting to resolve the latest dispute between Bogota and Caracas over Colombian rebels allegedly operating in Venezuela.

Both Nestor Kirchner, the former president and secretary general of regional grouping Unasur (the Union of South American Nations) and Cristina Fernandez de Kirchner, the incumbent president and Nestor’s wife, held talks with Juan Manuel Santos, Colombia’s president-elect this week.

Nestor said that his meeting with Santos, who was in Buenos Aires as part of a regional tour, was "fruitful", while Cristina talked of "establishing dialogue".

Nestor has conducted a series of phone calls with Alvaro Uribe and Hugo Chavez, Colombia and Venezuela’s incumbent presidents respectively, and other Latin American leaders on the issue.

He is also chairing Unasur's meeting on Thursday in Quito, Ecuador’s capital, in a special session to try to ease tensions.

The two Kirchners additionally had separate meetings this week with Nicolas Maduro, Venezuela’s foreign minister.

Maduro said that he had "great confidence in the political and moral authority" of the ex-president.

Nestor will travel to Caracas on August 5 to meet Chavez before going on to Bogota to visit Uribe. Christina will also meet Chavez and Santos in the coming week.

Alleged bases

Last week, Colombia accused Venezuela of harbouring about 1,500 left-wing Colombian rebels, and produced their camp coordinates, photographs and videos to support his case.

It said that the 87 alleged bases of the Revolutionary Armed Forces of Colombia (Farc) and the National Liberation Army (ELN) are used for training fighters in kidnapping and explosive techniques in the country.

The evidence was made at a special meeting of the Organisation of American States (OAS) in Washington.

The claims were likely authorised by the US, which has provided billions of dollars in anti-narcotics finance during Uribe’s eight year term, and in any case were subsequently given Washington’s public backing.

Venezuela denied the accusations, stating that Colombia is attempting to create the conditions for a US invasion in the country.

Caracas immediately cut diplomatic ties with Bogota and then sent about 1,000 soldiers to the nations’ border region.

The assertion is far from novel – Caracas has consistently been accused of links with the Farc – but it forces the region to address the issue and in particular nations such as Brazil which have held back from criticising Chavez in the past.

Jingoistic rhetoric

The Andean nations’ poor relations are also far from unprecedented.

Chavez has threatened force on Colombia and broken diplomatic ties with Bogota in the past.

Last year, the leader of the Bolivarian Revolution partially froze trade with his neighbour over the US establishing military bases for the fight against the drugs industry in Colombia.

Some local analysts have said that the incident will be beneficial to the populist Chavez who faces legislative elections in September and rarely misses a chance to use jingoistic rhetoric to distract from problems at home, such as increasing crime and failing infrastructure.

But Santos, who will take office on August 7, appeared to be attempting to thaw the tense relations, after arranging a meeting between Maduro and Maria Angela Holguin, his new foreign minister.

Reconciliation would be a bonus for his standing in Latin America. So far he has not commented publically.

As one of the instigators of the free trade deal between Bogota and Caracas, Santos would realise the value of cooperative ties.

Colombian trade to Venezuela – which over a year ago was its second biggest trade partner – is down by about 70 per cent now from a year ago, although it has compensated for some of this loss in generating trade in Chile, the Caribbean and Central America.

Bringing the issue to light in the final days of Uribe’s tenure may have cleared any dirty work Santos would otherwise have to do.

Political ambitions

Maduro visited Unasur members Brazil, Chile, Paraguay, Uruguay and Bolivia, as well as Argentina this week.

He requested assistance to establish a peace plan including a "political dialogue" with the Farc and ELN.

Bogota has since reasserted its offer of amnesty to left-wing fighters.

It now remains to be seen what Argentina and Unasur can do to rectify the issue.

In Buenos Aires, the situation bolsters the Kirchners’ political ambitions, with it being mooted that Nestor will run for the presidency in 2011.

Cristina would not be permitted to undertake two consecutive terms under the consitution.

Questioned last week about who will lead the pair’s Peronist party ahead of the polls, Cristina said it will either be a "Mr or Mrs Penguin" in reference to the local media’s fondness to likening her to the aquatic bird.

It is unlikely that Unasur can do anything to halt Chavez’s outspokenness in the face of oncoming elections or Colombia’s disgruntlement.

It is more interesting that the grouping is being proposed as the setting for resolution, progress and stability, conveying its continued usurpation of the OAS – of which the US is a member, unlike Unasur – as the region attempts to re-configure its institutions to the left.

An ideological battle is also underway between Chavez’s socialist revolution and the right-wing, free market approach of Bogota.

The nations’ leaders previously ignored such differences in favour of trade and investment benefits.

And although the clash may be calmed over the next few weeks it is hard to see how harmony will be brought about in the long-term.

Follow Rhodri Davies on Twitter: @rhodrirdavies