Dima Khattib, Al Jazeera's correspondent in Caracas, the Venezuelan capital, said on Friday that "given the history between Colombia and Venezuela [this row] is not that serious".

Hugo Chavez, the Venezuelan president, has said he believes Colombia is plotting with the US to ferment unrest in his country.

'Hiding in Venezuela'

The Colombian government presented photos and video that supposedly shows guerrillas training in Venezuela, but they could not be authenticated, our correspondent said.

"I have been to the border areas [in Venezuela] looking for Farc rebels and the camps and never found anything. If the Colombians were really to give proof, it would be quite a big story," she said.    

Colombia's government said that Ivan Marquez, a member of Farc's seven-member secretariat, is among the rebels hiding in Venezuela.

Two years ago, Colombian forces attacked a Farc camp in neighbouring Ecuador, killing a rebel leader and prompting Ecuador and Venezuela to break off ties with Colombia.

Juan Manuel Santos recently won the presidential electionin Colombia and some analysts hoped his victory would ease tensions with Venezuela.

Prior to the new allegations, Santos invited Chavez to his swearing-in ceremony and Chavez said he was considering the invitation.

Venezuela has not said anything about the ceremony during this latest row, which means that Chavez may still attend, our correspondent said.

In a statement on Friday, Venezuela's foreign ministry said: "We hope the new government will accept as a top priority the proposal of a Colombia peace plan, which will let all of us in South America usher in a lasting solution to the armed conflict that affects our brother country."