When Hugo Chávez died eight months ago, hundreds of thousands of bereaved Venezuelans flocked past his open coffin to say their final goodbyes. It is no surprise then that a recording of the late leader claiming to be alive would cause a stir.

In the audio recording, a voice similar to Chávez's says he is being held captive against his will, accusing his former friends of betraying him.

President Nicolás Maduro to declare it the latest attempt by the opposition to destabilise the government.

Maduro, chosen by Chávez as his preferred successor, accused the main opposition party, Primero Justicia, of faking the clip, in which a weakened Chávez calls his brother, Adan Chávez, a state governor, to say he is alive.

"They [the opposition] have no respect for the memory and the love that the Venezuelan people have for Hugo Chávez and they are capable of inventing these recordings," Maduro said at the weekend.

The voice claiming to be Chávez says he is convalescing and his closest friends betrayed him. It pleads with his brother to tell Venezuelans the truth.

"Who would have thought our enemy was within? How many hugs they gave me, how many handshakes and how many lies," the voice says. "I want you to tell the boys, that today, September 16, I am more alive than ever."

The recording's veracity was firmly denied by Adan Chávez. "This disgusting montage has prompted some to believe that Chávez didn't die and that he is hiding. Others think that this recording was done before his death. It is all a great lie.

"Hugo Chávez was buried alongside the love of his loyal and revolutionary people, and he never sent me a message of this type."

The president of the national assembly, Diosdado Cabello, said the release of this recording was a political tactic aimed at discouraging United Socialist party supporters from voting in the December elections.

"This is clearly to demoralise our people, to inhibit them like they did in the April polls," Cabello said of the presidential elections that gave Maduro a razor-thin victory over opposition leader, Henrique Capriles.

But some political analysts suggest the recording could have been released by the government. "It is fundamental to monopolise the control [of Chávez's image]. It also appears clear that this is an opportunity to blame the opposition of an attempt to destabilise with which they maintain a polarisation that benefits them," says Luis Vicente Léon, one of Venezuela's leading political consultants.

This is not the first time Chávez has been imitated. During his first presidential campaign in 1998, a clip with a voice claiming to be him and threatening to "fry his opponents' heads" caused a national commotion.