Australian Greens senator Sarah Hanson-Young has announced she is seeking her party's leadership after Larissa Waters abruptly stepped down, citing a significant decline in her health due to kidney disease. Hanson-Young, the party's longest-serving federal MP, pledged to take a combative stance against both the Labor government and the far-right One Nation (a populist party led by Pauline Hanson that has recently overtaken the Greens as Australia's third political force). The new leader is expected to be chosen by Thursday at a party retreat in Sydney, with deputy leader Mehreen Faruqi and defence spokesperson David Shoebridge also considered frontrunners for the role.