( CNN ) Venezuelan President Nicolas Maduro says his government had blocked what he called a U.S.-backed coup plot that included plans to attack the presidential palace with a military jet . `` It is the government of the United States that is behind the plans of destabilization and coups against Venezuela . I have come here to denounce it . ... We have dismantled a coup attempt against democracy , against the stability of our homeland , '' Maduro said in a televised address Thursday . `` It was an attempt to use a group of officials from the air force to provoke a violent act , an attack . '' He did n't name which members of the military were allegedly involved , but claimed that the U.S. government and right-wing opposition groups in Venezuela were behind the plan . U.S. State Department spokeswoman Jen Psaki on Friday dismissed the claims . `` These latest accusations , like all previous such accusations , are ludicrous , '' Psaki said . `` As a matter of long-standing policy , the United States does not support political transitions by non-constitutional means . Political transitions must be democratic , constitutional , peaceful and legal . We 've seen many times that the Venezuelan government tries to distract from its own actions by blaming the United States or other members of the international community for events inside Venezuela , '' Psaki continued . `` These efforts reflect a lack of seriousness on the part of the Venezuelan government to deal with the grave situation it faces , '' she said . Venezuelan authorities detained those involved in the plot on Wednesday and Thursday , Maduro said . Maduro said the plot centered around a plan to commandeer a Super Tucano jet and attack the presidential palace this week , or a public demonstration that he was attending . Other buildings were on the target list , he said , including the teleSUR network 's headquarters and Venezuela 's Defense Ministry . U.S. officials , he said , provided visas to those involved in the plot and paid them in dollars . It 's not the first time the Venezuelan leader has lobbed serious accusations against the United States . Shortly after former President Hugo Chavez 's death , he suggested that the United States might have poisoned the socialist leader to cause the cancer that killed him . He expelled a group of U.S. diplomats from the country last year and accused the Pentagon and CIA of conspiring against him . The State Department has repeatedly rejected such accusations . Last year , it said Maduro 's claim that U.S. officials had conspired against the Venezuelan government was `` baseless and false . '' On the day of his election in 2013 , Maduro vowed to use an `` iron fist '' against any coup attempts against his government . On Thursday , Maduro said the latest coup plot was tied to a coup attempt last year that involved several Venezuelan air force generals . The accusations come as opposition protesters mark the one-year anniversary of a wave of anti-government demonstrations that rocked Venezuela last year and led to the arrest of opposition leader Leopoldo Lopez . CNN 's Michael Roa , Diane Ruggiero , Michael Martinez and Laura Koran contributed to this report .
Accusations are `` ludicrous , '' U.S. State Department spokeswoman says . `` We have dismantled a coup attempt , '' President Nicolas Maduro says in a televised address . He says Venezuela 's right-wing opposition groups and the U.S. government were behind the plot .