The legal age of marriage and civil partnerships in England and Wales is to be raised from 16 to 18, in what is hoped will stop child brides being forced into marriage.
Currently, 16 and 17-year-olds can marry with parental consent, but campaigners had warned this legal loophole had been exploited and used to coerce some young people into child marriage.
Proposed by Pauline Latham, the Conservative MP for Mid Derbyshire, the new law could see adults who facilitate the marriage of children face up to to seven years in jail and receive a fine.
She said that the legislation, which would apply to cultural or religious marriages that are not registered with the local council, will "transform the life chances of many girls".
The legislation, which had its third reading in the House of Lords on Tuesday, will receive Royal Assent later this week, meaning it will become law from then.
It will not affect the validity of any marriages or civil partnerships that happened before the legislation comes into effect.
The legislation does not apply to Northern Ireland, where you still require parental consent to marry aged 16, and Scotland, where you do not.
Campaigners have welcomed the new law as an important safeguard against young girls being coerced into child marriage, a practice which they say causes lifelong damage.
"Although forced marriage has been a criminal offence for some time, the law was failing to protect all children from being coerced into child marriages," Diana Nammi, executive director of IKWRO, a women’s rights organisation, told ITV News. "It is often so difficult for a child to understand and recognise coercion and then to seek help." "Now, with the new law it will be absolutely clear to safeguarding professionals that they must protect all children against all types of child marriage (whether registered or not)."
Payzee Malika was coerced into marriage aged 16 and campaigns against child marriage after her sister, Banaz, was murdered in a so-called "honour killing".
"There has not been a single moment in this journey when Banaz was not at the forefront of my thoughts," she tweeted. "Every day I thought of her. I fought for her. This law could have saved her."
Figures released by the ONS last year show 140 teenage girls and 43 teenage boys were married with parental consent in 2017, a number that has generally declined in recent years.
But it is widely believed that this recorded data does not capture the scale of those being wedded in non-legal religious and customary ceremonies.
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