Producing fake pornographic images based on pictures of real people should be made a criminal offence in an amended bill to tackle upskirting, an academic expert has argued.

The government has agreed to sponsor the legislation after its initial progress was halted by a Tory MP on Friday, but Clare McGlynn, a law professor at Durham University who specialises in the legal regulation of pornography and image-based sexual abuse, said there was now an opportunity to introduce broader “future-proofed” legislation.

She argued that the bill should penalise those who created so-called “deepfake” images that if shared could have a devastating impact on an individual.

“The upskirting bill is a welcome first step towards a more comprehensive response to image-based sexual abuse, but when a government tries to legislate on something quickly there is a risk that an opportunity to have a proper look at the problems raised by new technology is missed,” McGlynn said.

Deepfake pornography is a growing form of online abuse which began with images of celebrity’s faces being digitally manipulated into explicit stills and videos. However, it has become increasingly easy for anybody to be targeted, with a number of apps specifically designed for the purpose emerging.

In May Davide Buccheri, a worker in the City of London, was jailed for 16 weeks for harassment after producing faked pornographic images in an unsuccessful attempt to discredit a female colleague.

But experts like McGlynn say English law is out of step with modern developments and it would be easier to bring prosecutions by making it a specific offence.

“It would be easy to extend the bill so that it covers images which have been altered too and clearly criminalise a practice that victims say they find incredibly distressing,” McGlynn added. A new law introduced in New South Wales, Australia, last year, was a model for what could be done, she added.

Theresa May confirmed at prime minister’s questions that the government would introduce the bill to ban the taking of upskirt photographs on Thursday, taking on the private members bill proposed by the Lib Dem MP Wera Hobhouse that was blocked on Friday after Tory MP Sir Christopher Chope objected.

With government time the bill is guaranteed to become law, and it becomes possible for sympathetic MPs to amend the legislation into related areas to widen its scope. The Labour MPs Jess Phillips and Stella Creasy are understood to be considering whether it is possible to achieve cross-party support for additional changes.

Ministers have already decided to amend Hobhouse’s bill banning upskirting to ensure that the most serious offenders will be placed on the sex offender register. As currently drafted, the bill proposes that offenders will be liable for up to two years in prison if found guilty of what May described as a “gross invasion of privacy”.

The professor also said she thought Hobhouse’s upskirting bill also placed too high a burden of proof on prosecutors because they had to show that a picture was taken for the purposes of sexual gratification or to cause distress when “the unfortunate reality is that these things are often done ‘for a laugh’” adding: “It’s not clear to me that the current proposed legislation will cover these situations.”