The head of the CIA Mike Pompeo has described anti-secrecy organisation WikiLeaks as a “non-state hostile intelligence service” that is often abetted by states such as Russia.
Russian military intelligence used Wikileaks to distribute hacked material during the US election, he added.
Earlier this month Wikileaks published details of what it said were CIA hacking tools.
The FBI and CIA have launched a criminal investigation into the leak.
“WikiLeaks walks like a hostile intelligence service and talks like a hostile intelligence service,” Mr Pompeo said, speaking at a Washington think tank.
“It overwhelmingly focuses on the US, while seeking support from anti-democratic countries and organisations,” he added.
Wikileaks responded by posting a screenshot of a tweet sent by Mr Pompeo last July, in which the then member of the House of Representatives referred to material contained in the Wikileaks release of Democratic party emails. The tweet has since been deleted.
US intelligence agencies say Russia stole emails from the Democratic party to try to tilt the election in favour of Republican Donald Trump.
However Wikileaks founder Julian Assange has said the release was not intended to affect the election.
The CIA has refused to comment on the Wikileaks release of papers said to detail a wide range of hacking methods including using mobile phones and smart TVs.
But former CIA boss Michael Hayden told the BBC the leak was “incredibly damaging” and had made the US “less safe”.
US officials say IT contractors are likely to have breached security and handed the documents to Wikileaks.
Mr Assange has said Wikileaks will give technology firms access to the full details of the alleged spying programmes so they can defend their products against the hacking.
The Wikileaks founder has been living in the Ecuadorean embassy in London since 2012 after seeking refuge there when he lost his appeal against extradition to the Sweden, where he faces rape allegations.
He says the sex was consensual and believes the allegations are politically motivated with the aim of having him extradited to the US to face charges over Wikileaks’s release of US military documents.
CIA chief Pompeo: Wikileaks ‘hostile intelligence service’