Bellfield abducted and murdered 13-year-old Milly Dowler in 2002, then killed Marsha McDonnell in 2003 and Amelie Delagrange in 2004.

He also tried to murder 18-year-old Kate Sheedy and has been suspected in other cases.

One of the UK's most notorious criminals, he is serving two whole-life sentences and can never be released.

There was anger when the 56-year-old looked set to get married in prison after becoming engaged to a female visitor two years ago.

It was reported the former wheelclamper and bouncer got down on one knee in front of wardens at high security HMP Frankland in County Durham.

Bellfield successfully challenged efforts to stop the wedding - and is said to have received up to £30,000 of legal aid to fight the case on human rights grounds.

The Ministry of Justice (MoJ) said last year there was no way to stop him and that it was determined to change the law.

It's understood Bellfield recently changed his marriage application to instead apply for a civil partnership.

The move is believed to have prompted the government to speed up the introduction of the new law, which comes in today.

The legislation is part of the Victims and Prisoners Act and applies to killers serving whole-life orders, currently more than 70 people including the likes of Rose West, Wayne Couzens and Lucy Letby.

Marriage requests could only previously be refused if a prison governor believed there were security concerns.

Read more from Sky News:
Rapist who posed as taxi driver to lure women jailed
Man jailed for stealing 'eye watering' amounts from aunt

"Victims should not be tormented by seeing those who commit the most depraved crimes enjoy the moments in life that were stolen from their loved ones," said Justice Secretary Shabana Mahmood.

"That is why I have acted as soon as possible to stop these marriages and give victims the support they deserve."

The justice secretary will retain the right to permit ceremonies in very exceptional circumstances, said MoJ officials.