London Mayor Sadiq Khan has accepted responsibility for the upsurge in violent crime across the capital as he blamed police cuts for making the situation worse.
Mr Khan insisted the problem was not confined to London, but part of a national wave.
Asked how he would respond to people who believe he bears personal responsibility for the surge in knife crime and violence, Mr Khan told LBC: "I'm the Mayor of London, I'm the Police and Crime Commissioner - I accept responsibility for what happens in our city.
"Security is the biggest concern that I have, it's the one thing that keeps me up at night - whether it's terrorism threats, whether it's the surge in serious violent crime.
"But I am not going to apologise for explaining the context. We have seen across the country an increase in serious violent crime. This weekend in Ipswich, a 17-year-old child lost his life because of a stabbing.
"We've seen in Liverpool, in Cardiff, in Manchester, shootings in daylight hours where teenagers have lost their lives.
"Over the course of the last three or four years, we've seen an increase in violent crime across our country. These are national problems that demand national solutions."
Mr Khan said the Government was ignoring the link between police cuts and an increase in crime.
"Whether it's the commissioner, whether it's chief constables, whether it's senior Home Office civil servants, all of us, except for the Government, now accept there's a link between cutting police resources and an increase in serious violent crime. That's not the sole reason by the way, but there's a link."
Mr Khan said the Metropolitan Police had fewer officers now than at any time since 2003, and that the Government was responsible for almost 80% of the force's funding.
"We can dance around about what proportion of responsibility is mine versus the Government, but you can't escape the fact you have fewer police officers now doing more work than they were in 2003."