Greece’s government has rushed to revise legislation that redefines rape after unprecedented criticism from activists, human rights groups and senior judicial officials.

The law, part of a new penal code submitted to parliament by Alexis Tsipras’ administration only weeks before snap elections, had raised fears of convicted rapists being treated more leniently.

In a move hailed as a historic victory by activists, the justice minister Michalis Kalogirou caved in on Thursday.

Less than 24 hours after women’s groups had converged on parliament in protest, he amended the bill, known as Article 336, clarifying that sex without consent would be considered rape and, as such, punishable under the law.

“Whoever attempts a sexual act without the consent of the victim is punished by imprisonment of up to 10 years,” the revised law states. It is expected to be put to MPs on Friday.

Reacting to the last-minute change, the head of Amnesty International’s Greece office, Eirini Gaitanou, said: “This is a historic victory, not just for the campaigners who have fought long and hard for this day, but for all women in Greece.

“The newly amended law finally recognises the simple truth that sex without consent is rape and makes it clear that physical violence is not required for the crime to be considered rape … [it] should give hope to people campaigning for consent-based laws wherever they are.”

Only a handful of countries have recognised that sex without consent should be treated legally as akin to rape. Once passed, Greece will become only the tenth country in Europe to enshrine that recognition in its criminal code.

Gaitanou said it was also imperative that guidelines were given to ensure police and public prosecutors enforced the legislation.

“It is now time for everyone involved in the criminal justice system to be given clear guidance as to how this change in the law must be implemented to make it easier for survivors to get justice,” she said.

Before the amendment there had been widespread fears the draft legislation would dramatically weaken laws on rape.

It categorised some rapes as a misdemeanour rather than a felony, and critics – including female members of Tsipras’ Syriza party - had argued that convicted rapists could face prison sentences of as little as three years.

In redefining the crime, the new bill all but ignored the issue of freely given consent and focussed instead on the use of violence, resistance involved and the physical threat posed to a victim’s life. Human rights groups had described the lack of emphasis on non-consensual sex as “deeply problematic” citing “involuntary paralysis” or “freezing” that experts have recognised as an instinctive response to sexual assault.

The women’s rights group Equality Now, which had called for the immediate withdrawal of the bill, had argued that the draft legislation offered wide scope in judicial interpretation.

Had it been applied, the law would also have amounted to a dereliction of duty for a country that had committed to criminalise non-consensual sexual acts under the Council of Europe’s Istanbul Convention, which Athens ratified last year.

“It is very welcome that the government listened to the voices of women’s rights advocates in Greece and other experts to make changes to the law,” Equality Now’s Europe director, Jacqui Hunt, said. “Anything that lets potential perpetrators of sexual violence off the hook creates an environment for further violence and does a huge disservice to the women affected.”