By Paul Gribben, BBC News
Julian Assange's wife says the WikiLeaks founder would not survive being extradited from the UK to the US.
His final appeal will be heard at the High Court in London on Tuesday and Stella Assange says he is physically and mentally extremely weak.
She told BBC Radio 4's Today programme that "this could very well be the final hearing for Julian".
Assange is wanted in the US on espionage charges and faces up to 175 years in prison.
The case is about him publishing thousands of classified documents in 2010 and 2011, which American authorities say broke the law and endangered lives.
He argues that the case against him is politically motivated.
Stella Assange told the BBC that if her husband loses Tuesday's High Court case in London, "there's no possibility for further appeal in this jurisdiction".
However, she did raise the possibility of applying to the European Court of Human Rights to try to secure an emergency injunction.
She suggested that based on similar extradition cases there would only be "a matter of 24 hours" in which to make such a legal move.
She told the BBC that stress caused by the case had left her husband physically and mentally "in a very difficult place" knowing that "anything could happen this week".
"This case will determine if he lives or dies, essentially."
Assange, an Australian citizen, has been kept at London's Belmarsh Prison since 2019 as the US extradition case proceeded.
In 2021, the High Court ruled that Assange should be extradited, and rejected claims that poor mental health meant he was at risk of taking his own life in a US jail.
The Supreme Court upheld that decision the following year and the then Home Secretary Priti Patel confirmed the extradition order.
Australia's parliament last week upheld a motion calling on the US and UK to release Assange ahead of this week's key hearing.
This story was originally published by the BBC.