Donald Trump has reclassified Cuba as a “state sponsor of terrorism”, citing the communist country's backing of Venezuela.
US secretary of state Mike Pompeo accused the Cuban government of providing support to murderers, bombmakers and hijackers, and harbouring American fugitives among other actions.
The Caribbean island was removed from the list by President Barack Obama in 2015, but Mr Trump has taken a harder line towards the country.
In a statement released on Monday, Mr Pompeo said: “With this action, we will once again hold Cuba’s government accountable and send a clear message: the Castro regime must end its support for international terrorism and subversion of US justice.”
Cuba called the move "political opportunism".
Cuban Foreign Affairs Minister Bruno Rodriguez tweeted: "We condemn the cynical and hypocritical qualification of Cuba as a state sponsor of terrorism, announced by the United States."
Most observers and many US allies are unimpressed by Trump administration claims that Cuba is guilty of sponsoring terrorism.They have condemned the move as the latest attempt by the outgoing president to hinder the incoming Biden team’s to carve out their own relationship when it takes office January 20.
President-elect Joe Biden has previously said he wants to improve US-Cuban relations.
Mr Biden's plans included allowing Cuban-Americans to visit family and send money.
President Obama began to normalise relations with Cuba in 2015. He called the decades-long US efforts to isolate the country "a failure".
As with Iran, Trump has sought to reverse many of Obama’s decisions involving Cuba. He has taken a tough line on Havana and rolled back many of the sanctions that the Obama administration had eased or lifted after the restoration of full diplomatic relations in 2015.
Since Trump took office ties have been increasingly strained, with his administration also suggesting Cuba may have been behind or allowed alleged attacks that left dozens of US diplomats in Havana with brain injuries starting in late 2016.
The announcement on was widely expected. The process for adding a country to the terror sponsor list requires inter-agency review and in most cases takes several months, meaning that Mr Biden could find it difficult to reverse quickly.
Cuba was first put on the list of state sponsors of terror in 1982 under Ronald Reagan’s presidency because of what Washington said was Havana’s long-running support for Latin American guerrilla groups.