Hundreds of honour violence and forced marriage crimes are going unpunished in London, according to new figures.

Data shows that police recorded 759 honour violence crimes and 265 forced marriages in the capital between 2015 and 2017 - but just 138 people were charged with offences.

The statistics also show that prosecution rates for both crimes have fallen in the past three years.

Charities and campaigners today said the figures were worrying when nationally statistics showed the number of women coming forward to make allegations was rising.

Diana Nammi, executive director of the Iranian & Kurdish Women’s Rights Organisation, which provides refuge for victims, said : “What makes it so alarming is that figures that we obtained through freedom of information requests show that, at the same time, since the criminalisation of forced marriage in 2014, many more people at risk than ever before are coming forward for help.

“As “honour” based violence is perpetrated by the victim’s own family and community there is a lot of pressure on victims to drop cases and too often justice is not seen. “London must not be a safe haven for perpetrators of these horrific, damaging crimes. We need to see much more action from the Mayor of London to tackle “honour” based violence and his priority must be to fund women’s rights organisations like IKWRO who are best placed to support victims and survivors who courageously come forward.”

The figures, obtained by London Assembly Conservative member Susan Hall, show there were 261 honour violence offences in 2017, compared to 232 in 2016 and 266 in 2015. A total of 35 people were charged with honour violence last year, compared to 36 in 2016 and 44 people in 2015.

There were 98 forced marriage offences in 2017, just two more than the previous year. There were 71 offences in 2015.

The data shows just six people were charged with offences of forced marriage last year, compared to seven in 2016 and 10 in 2015.

Ms Hall claimed the figures showed the Met needed a fresh approach to honour crime.

She said : “Honour violence and forced marriage are appalling and archaic practices that have no place in a modern city like London.

“The charge rate for these offences is appallingly low. If the police are to overcome the barriers of witnesses being too scared to give evidence and of communities unwilling to co-operate, they must develop better relationships with those affected by these crimes.

“The Met has done some excellent work in recent years to improve the number of rape victims coming forward. We need a similar approach here so that victims feel more confident they will be protected from the abusers in their community – and that figures within their community will support them too.”

Charity Karma Nirvana, which runs a helpline for victims, said : “The Met should seek the engagement of experienced agencies to refresh their approach to deal with such complex cases.

“Karma Nirvana receives its highest number of calls from London, so closer collaborative working is key to better protect victims. Police are able to use such powers to send a strong message to those communities unwilling to co-operate.”

Jasvinder Sanghera, head of the charity Karma Nirvana, which runs a helpline for victims, said : “I am totally dismayed to find that year on year so few cases resulted in charges. It is a mockery of the law especially when we know this reporting remains the tip of the iceberg.

“Karma Nirvana receives over 800 calls a month to the national helpline and London remains its top calling area. My hope is this is a wake-up call. The Met should seek the engagement of experienced agencies to refresh their approach to deal with such complex cases.”

Inspector Allen Davis, who leads on the Met’s honour crime partnership team, said : “Responding effectively to all forms of Honour Based Abuse is a priority for the Metropolitan Police. Simplistic correlations between reported offences and convictions are sometimes unhelpful and undermine the confidence of victims to come forward and seek the help and support they desperately need. “It is essential that the complexity and challenges of dealing with these hidden crimes are fully understood.

“We work closely with statutory and non-statutory partners to ensure that victims have the confidence to come forward and report it, that when they do victims are supported and feel safe, and when possible, perpetrators are prosecuted for the often horrific harm that they cause.”