Jebina Yasmin Islam, in an interview with ITV, demanded to see change for women after her sister was killed while making a five-minute journey to a pub to meet a friend in south-east London on September 17.
She said the death of her sister still “hurts inside” as she asked Sadiq Khan and Boris Johnson to step up when it comes to women’s safety.
“Boris Johnson needs to do something,” Jebina said.
“Sadiq Khan needs to implement something for us to feel safe to walk the streets alone. We should not be going home extra early just because we don’t feel safe - we shouldn’t.
“We are independent, we live in a country where we can walk alone - but we can’t because of what’s happening and what’s happened to my sister.
“We need to make sure this does not happen again. Boris, Sadiq Khan - they need to step up.”
The Mayor of London responded to stress women should not have to change their behaviour and vowed to root out the “abhorrent behaviours”.
Mr Khan set out what he is doing to make women and girls feel safe, including a £60.7m in programmes dedicated to tackling all violence against females.
A spokesperson for the Mayor of London told The Standard: “The Mayor is devastated by the death of Sabina Nessa and strongly believes all women should have had every right to feel safe going about their lives.
“The heart-breaking murders we have seen in the capital must re-focus all of our minds on the unacceptable ways in which our society views and treats women. The Mayor is clear that it’s not women who should have to change the way they live their lives – it’s men that need to change and that’s why we must root out these abhorrent behaviours.
“Women and girls in London should be safe and feel safe – whatever the time of day and wherever they are in our capital. That’s why the Mayor has invested a record £60.7m in programmes dedicated to tackling all violence against women and girls. This has funded crucial support services for victims, delivered programmes that tackle the behaviour of perpetrators of abuse and violence, and provided training to improve the police response to domestic abuse and violence against women and girls.
“The Mayor has also been clear that if we are going to truly fix the problem, we need to see a fundamental and enduring cultural shift, and he is committed to working tirelessly to make sure women and girls are safe in our city.”
The death of the teacher sent shockwaves around the country.
At the weekend, her family gathered to mark what would have been Ms Nessa’s 29th birthday.
Garage worker Koci Selamaj, 36, has been charged with Ms Nessa’s murder.
Recorder of London Judge Mark Lucraft QC ordered Selamaj to return to court for a formal plea hearing on December 16. A trial date has not yet been set.