Home Secretary James Cleverly has defended the government's delay in announcing legislation to toughen up a ban on zombie knives.
The government is introducing new legislation on Thursday to "close the loophole" on the weapons, which were first banned in 2016.
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Ministers are aiming to make it harder for the weapons to be sold legally, aiming for it to be against the law to possess, sell, manufacture or transport the blades.
Zombie knives are defined in law as blades with a cutting edge, a serrated edge and "images or words that suggest that it is to be used for the purpose of violence".
The government announced five months ago that they planned to introduce tougher regulations.
Asked why it had taken so long, Mr Cleverly said: "We have already taken action to make the carrying of zombie knives illegal.
"When I became home secretary, I made the immediate decision to go further to put forward this secondary legislation to support what we've already done to make the possession of zombie knives illegal and to close that loophole.
"So I'm very pleased we're taking action now, and we'll be determined to get these knives off the streets."
A surrender scheme will be introduced ahead of the new regulations coming into force in September.
The government also wants tougher penalties for those who possess the knives - increasing the maximum sentence from six months to two years.
Labour promises 'no more weak warnings'
As Mr Cleverly made the announcement, the Labour Party said it would launch a £100m plan to tackle knife crime if it were to enter government.
The party also promised "real consequences" for knife crime - and an end to the "empty warnings and apology letters" for those guilty of knife possession
"Too many young people are being drawn into squandering their life chances by getting involved in crime. A government that I lead won't think we can press release away soaring youth crime," Sir Keir Starmer said.
Reacting to the announcement from Mr Cleverly, shadow home secretary Yvette Cooper added: "Six Tory home secretaries have promised these changes, and still they don't go anywhere near far enough and don't match Labour's plans for a comprehensive ban.
"Dangerous weapons like ninja swords, which have been used to kill teenagers, will still be available on Britain's streets.
"Still, law-breaking online platforms who profit from these illegal sales are being let off with a slap on the wrist instead of facing criminal sanctions. Labour would close these glaring loopholes in the government's plans."
Home Office minister Chris Philp branded the Labour plans as "just another reheated pledge from the Labour Party using money they have already spent seven times".
He added: "They cannot say what their plan actually is. Because just like their reckless £28 billion-a-year spending spree they don't have a plan - meaning higher taxes for the British people."