Labour’s Sarah Jones vowed to keep cracking down on knife crime after she retained her seat in Croydon Central.
Knife crime has been rife in London with more than 20 teenagers stabbed to death in the capital this year.
Ms Jones said the number of stabbings was falling and she was determined to keep making progress.
She said: “We’re hoping this is a trend and not a short-term effect.
“We’re doing a lot of things differently in Croydon, putting youth workers into A&E and opening the big legacy youth zone, and adding more police in the centre of the town.
“I will carry on fighting for more police and for more funding for new services for mental health and addressing all the reasons people make bad choices in the first place.
“There is a battle still to be had on this issue and I will carry on fighting it.”
Ms Jones said her methods against knife crime have been successful.
A July 2019 Metropolitan Police report cited a 17% decrease in knife crime in Croydon.
Knife crime has reached record highs in England and Wales. Figures released in October show an increase of 7% on the previous 12 months.
Theresa May said she considered knife crime a priority while she was Prime Minister and held a summit at Downing Street in April to tackle the epidemic, which Ms Jones attended.
However, since Boris Johnson took office in July, the fight against knife crime has been put on the backburner, according to Ms Jones.
She insists she would be willing to help and assist the new government and London Mayor Sadiq Khan to stem the rise in knife crime across the capital.
Ms Jones said: “Before Boris Johnson was elected we were beginning to have some success at national government level getting funding.
“Theresa May had a knife crime summit which I went to and she was beginning to involve the departments of health and education and that all fell by the wayside when Boris Johnson was elected but we want to carry on making the case.
“I will be delighted if I can work with government or the mayor to get the numbers down because it is devastating when people’s lives are ruined unnecessarily.”
Ms Jones has served as Labour’s shadow minister for housing, communities and local government since May 2018.
She is also the founder and chair of the All-Party Parliamentary Group on Knife Crime, a group comprised of over 40 MPs and peers.
Ms Jones held senior campaigning roles within the NHS, the London 2012 Olympics and worked as head of campaigns for Shelter prior to her 2017 election in Croydon Central.
Despite her victory Ms Jones was disappointed with her party’s performance overall, as Labour slumped to its worst result since 1987.
The result prompted leader Jeremy Corbyn to announce he would step down ahead of a future General Election.
However, Ms Jones refused to be drawn on how her party should move forward.
She said: “We believed we had a manifesto that would have really radically improved people’s lives and the people did not put their faith in that they did not have faith in us to deliver.”
“We have to start by asking by questions and listening to what people have to say rather than jumping to conclusions the night of the event itself.”