London’s mayor has warned of a rise in shootings and stabbings amid concerns that the increasing cost of living could lead to more violence and make it easier for gangs to lure vulnerable young people.

Sadiq Khan said millions of pounds more were being put into schemes to turn people away from violence. The Labour mayor has been criticised by some for his record on crime.

Khan said more than half of shootings in London and nearly a quarter of homicides were believed to be linked to gangs. Gang exit schemes are being boosted by £2m.

The mayor said: “I am concerned about a potential increase in violence this summer as the cost of living crisis deepens and threatens to reverse the progress we have made in tackling violent crime. Violence, like poverty, is not inevitable and the government must now do much more to show it shares my commitment to building a fairer, safer London for all.”

The mayor said he had put a total of more than £8m into a gang exit programme that had helped hundreds of young people to move away from crime.

The scheme, led by the charity Safer London, has helped 430 young people, with 83% significantly reducing or leaving gang activity.

Sherry Peck, who leads Safer London, said she believed poverty, alienation and trauma left young people vulnerable to being groomed and recruited into violence.

“There is so much being done to stop an increase in violence, but what we know is that social injustice and inequality are the drivers of increased violence,” she said. “It’s important to understand many young Londoners are growing up in incredibly toxic environments, which makes them more susceptible to violence and exploitation.”

The fight to rescue vulnerable children can start with a youth worker meeting them at a place where they feel safe, such as the back of a bus, or a park bench.

Symone, a Safer London caseworker, said: “This usually includes meeting in a coffee shop, library, or even a park or bus, and to be honest it’s more effective than meeting in an office environment, which can feel too formal for these children and young people.

“Meeting them in places of their choosing is an essential part of building that trust and making sure they are involved in the decision making from the onset.”

There is concern nationally about spiralling living costs leading to a rise in crime. In May, Andy Cooke, the chief inspector of constabulary, warned of an increase in thefts and other acquisitive crime as the economic crisis deepens.

In a Guardian interview, Cooke said: “The impact of poverty, and the impact of lack of opportunity for people, does lead to an increase in crime. There’s no two ways about that.”

Privately, police chiefs are clear about the link between poverty and crime.