Previous ruling said reporters have no privilege to safeguard confidentiality leaving Risen to reveal his source or go to jail

The Obama administration is trying to dissuade federal judges from giving the New York Times reporter James Risen one last chance to avoid having to disclose his source in a criminal trial over the alleged leaking of US state secrets.

The Department of Justice has filed a legal argument with the US appeals court for the Fourth Circuit in Richmond, Virginia, in which it strongly opposes any further consideration of Risen's petition. Risen's lawyers have asked the court to convene a full session of the 15-member court to decide whether the journalist should be granted First Amendment protection that would spare him from having to reveal the identity of his source to whom he promised confidentiality.

A three-member panel of the same court last month issued a 2-1 majority ruling in which they found that reporters had no privilege that would safeguard the confidentiality of their sources in a criminal trial. The judgement leaves Risen, a prominent investigative reporter specialising in national security issues, facing the prospect of having to break his promise to his source or go to jail.

The legal crunch emerged from Risen's 2006 book, State of War, in which the author reveals details of the CIA's attempts to foil Iran's nuclear programme. James Sterling, a former CIA employee, is being prosecuted under the Espionage Act for the criminal disclosure of the information – one of seven officials to face the severe charges under the Obama administration including Chelsea Manning who has been sentenced to 35 years in military jail as the WikiLeaks source.

In a 26-page filing, the US prosecutor Neil Macbride and his team argue that Risen has no grounds to be offered a full hearing of the appeals court because there is no such thing as a reporters' privilege in a criminal trial. They insist that the New York Times journalist was the only eyewitness to the leaking crimes of which Sterling has been charged and under previous case law has no right to claim First Amendment protection.

"Risen's eyewitness testimony is essential proof of the disputed identity of the perpetrator that cannot be duplicated or replaced by other evidence in the case," MacBride writes.

The DoJ's robust attempt to block any further legal discussion about Risen's plight will add to the impression that the Obama administration is determined to stamp on official leaking regardless of its implications for press freedom – a syndrome that some critics have dubbed a "war on whistleblowing". Risen's lawyers argue that the hardline approach conflicts with the Justice Department's own recent guidelines in which it talks of a need for balance between pursuing leakers while "safeguarding the essential role of a free press in fostering government accountability in an open society".