A former partner of Greens senator Jordon Steele-John has been arrested on stalking and extortion charges.

The 40-year-old woman was charged with one count of aggravated stalking with intent to intimidate Steele-John and one count of demanding property by written threats.

She is expected to face Perth Magistrates Court on Thursday.

Steele-John is on leave from the Greens after seven party members wrote to leader David Shoebridge on October 15 urging action on allegations about the Western Australian senator’s behaviour with women spanning nearly a decade.

Steele-John vehemently denies any wrongdoing. The WA Greens are investigating the allegations.

In a lengthy letter posted to his social media three days after the allegations emerged, Steele-John accused Shoebridge of effectively forcing him to take leave and said he was the victim of a years-long smear campaign from within the Greens.

He later clarified he was on leave and did not appear at recent Senate estimates hearings in Canberra, where he is usually prominent as the Greens’ disability spokesman.

He has been contacted for comment on the charges laid against his former partner.

-AAP