The former partner of Cecilia Haddad, whose fully clothed body was found in a Sydney river two months ago, is officially wanted over her murder.

NSW Police have secured a warrant for the arrest of Mario Marcelo Santoro, who flew back to Brazil the same weekend the 38-year-old was found floating in the Lane Cove River.

The warrant means NSW Police would charge Mr Santoro with murder if he was in Australia.

Mr Santoro is a prime suspect in the investigation. However, the NSW warrant doesn’t guarantee Brazilian authorities will hand him over to face charges in Australia.

The warrant puts the Australian government in a position to negotiate with Brazilian counterparts to bring Mr Santoro to justice over the murder of one its own citizens in Australia.

Australia and Brazil have a long-standing extradition treaty that would nominally pave the way for Mr Santoro to be brought back to Australia.

However, the process could be complicated. On constitutional grounds, Brazilian authorities generally do not act on orders for a citizen to be extradited to face alleged offences committed in foreign countries.

“The Australian government does not disclose whether it has made, or intends to make, an extradition request to a foreign country until the person is arrested or brought before the court in a foreign country,” the federal Attorney-General’s Department said in a statement on Wednesday.

Nor could NSW Police comment further on the investigation, a spokesperson said in a statement on Wednesday.

Kayakers discovered Ms Haddad’s clothed body in the Sydney river near Woolwich on April 29, about the same time Mr Santoro flew back home to Rio de Janeiro.

Investigators confirmed in May that Ms Haddad had asked Mr Santoro to move out of her Ryde apartment, in Sydney’s north-west, in the weeks before her death.

Brazilian-born Ms Haddad arrived in Australia more than a decade ago. She moved to Sydney in 2016, and worked in mining and logistics.

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