Deputy director of public prosecutions Eva-Marie Persson will hold a press conference in Stockholm on Monday to announce her decision.

Assange is currently in prison in Britain after he was arrested by police last month following seven years in Ecuador's London embassy.

Sweden's legal tussle with the Australian has dragged on for nearly a decade after he was accused by two Swedish women of sexual assault and rape in 2010.

The statute of limitations ran out on the sexual assault allegations in 2015 and the prosecutor dropped the investigation into the rape allegation in 2017 because Assange was holed up in the Ecuadorian embassy, where he had taken refuge to avoid extradition.

The prosecutor said at the time the investigation could be reopened if the situation changed.

After Assange's arrest last month, the lawyer representing the woman who accused Assange of rape asked for the investigation to be reopened.

"At (a) press conference, the prosecutor will announce her decision, which will formally be made immediately before the press conference," Sweden's Prosecution Authority said in a statement on Thursday.

Assange, who denies the allegations against him, fought through the British courts to get the Swedish extradition order and the preliminary investigation dropped.

He sought asylum in the Ecuadorian embassy in 2012 while on bail after losing appeals against his extradition to Sweden.

His lawyers said he feared that should he go to Sweden, authorities could hand him over to the US to face prosecution over WikiLeaks' massive release of sensitive military and diplomatic documents.

In April, Ecuador withdrew its grant of asylum and Assange was arrested by British police.

Hours later, US officials announced he had been charged with conspiracy to commit computer intrusion and requested his extradition.

Last week, a British court sentenced Assange to 50 weeks in prison for breaching his bail.

Australian Associated Press