New 'two strike' knife possession law will land an extra 1,000 offenders in prison a year

Those convicted of carrying knives will face an automatic six-month sentence after their second conviction

Those convicted of carrying knives more than once will receive an automatic six-month sentence after their second strike (Getty)

The government is set to implement a 'two strike' system in an effort to cut knife crime, which will see repeat offenders being given mandatory six month prison sentences for carrying a knife.

The new policy was blocked by the Liberal Democrats during the last government, and the government claims that it will jail an extra thousand offenders a year.

Under the new measure, adults convicted for carrying a knife, who have been convicted of the same crime before, will face a prison sentence of at least six months, with a four year sentence as the maximum.

Young offenders under the age of 18 will face a four month sentence and training order. Judges will still be able to use their discretion if they think the sentence would be unjust, however.

A man is given emergency medical attention after being stabbed at Notting Hill Carnival in 2011 (Oli Scarff/Getty Images))

It is illegal to carry a knife in public without good reason, although this is not a blanket ban on all kinds of knife - people are totally free to carry a knife with a folding blade that is less than three inches long, similar to what might be found on a Swiss Army knife.

London mayor Boris Johnson and the Metropolitan Police Commissioner Bernard Hogan-Howe have been pressing for the new law since the election, due to a rise in stabbings in London.

Currently, around a third of those convicted of illegally carrying a knife were given an immediate jail sentence. Government assessments suggest that each year, around 1,300 people who have previous knife possession convictions, are caught in possession of a knife without getting further jail sentences.

Although the numbers of offenders who will be jailed by the new law seem low when spread across the country, they will have a big impact on the prison system. Ministers estimate that an additional 1,000 people a year will be jailed as a result of the new sentences, which will put extra strain on the already overcrowded prison system.

The measure was proposed during the last government but was blocked by the Liberal Democrats, with Nick Clegg claiming it was nothing more than a "headline-grabbing solution" that would prove impractical and would not address the root causes of knife crime.

The measure will come into force from 17 July. Justice Minister Mike Penning said: "With this new measure we are sending out the strongest message to offenders: repeatedly take a knife on to our streets and expect to go to prison."