The most serious cases of revenge pornography – putting sexually explicit images of former partners online – should be prosecuted under laws which carry a maximum sentence of 14 years, new guidance from the Crown Prosecution Service suggests.

The guidelines say that prosecutions should not be brought under obscenity laws but on the basis of the menace and humiliation intended, and in the most serious cases, where intimate images are used to coerce victims into further sexual activity, under the Sexual Offences Act 2003.

The CPS advice, described as “clarification” as opposed to signalling a fresh approach, comes amid calls from some MPs for a new law specifically to combat revenge pornography.

A spokesperson for the CPS said: “No one should have to suffer the hurt and humiliation of ‘revenge pornography’ – a nasty and invasive crime that appears, anecdotally at least, to have increased as social media use has gone up.

“The CPS prosecutes these cases using a range of current laws, and we have now clarified our legal guidance to set out clearly how these cases should be brought to court.

“Due to the very personal nature of ‘revenge pornography’, prosecutors are being asked specifically to consider the impact on the victims involved.

“The new guidance also makes clear that the context of each case needs to be considered alongside current guidelines to ensure that the most appropriate legislation is used when prosecuting. The public, and indeed those intent on attacking former partners in this way, can now see clearly that this is a crime that can and will be prosecuted.”

Revenge pornography usually involves sexually explicit images of ex-partners being sent out without their consent.

Such images are often accompanied by private information including their name, links to social media profiles and address. They are shared online with the intent to cause distress or harm to the individual.

The guidance states the issue for prosecutors should be whether the message or communication is grossly offensive, indecent, obscene or false, not whether the image itself is indecent or obscene.

Last week, figures uncovered by the Press Association showed schoolgirls were among those targeted, while adults had been blackmailed into having sex with their tormentor after indecent – previously private – images were put on the internet.

There were 149 allegations of crimes involving revenge pornography during the last two-and-a-half years, according to the eight police forces in England and Wales with data on it.

The figures, believed to be the first into its prevalence, showed the vast majority of victims are women – with only six incidents resulting in any sort of police caution or charge.

The issue was brought into sharp focus after celebrities including pop stars Rihanna and Tulisa Contostavlos fell victim to the cruel craze.

In September, Labour MP Geraint Davies proposed that people who are complicit in the distribution of revenge porn should be prosecuted.

The criminal justice and courts bill must undergo further consideration in the Lords before any amendments are debated by MPs.