The measures, which will come under a new proposed law called Jade's law, come in response to campaigning from the family of Jade Ward, who was stabbed and strangled by her partner Russell Marsh in 2021 while their children were asleep.

Despite being sent to prison, Marsh still retains rights to request school reports and medical details of his children and could even stop them from seeking therapy or travelling abroad - in what Alex Chalk, the justice secretary, has called an "injustice in our family justice system".

Mr Chalk is expected to tell the Conservative Party conference that under the new law, a person who is convicted of the murder or voluntary manslaughter of a person with whom they share children will lose their parental rights.

It also means that family members will no longer have to apply to the family court to request that parental responsibility is removed.

Mr Chalk is expected to say: "Jade Ward's case and the moving campaign of her family has exposed an injustice in our family justice system, one that we are committed to fixing.

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"Murderers who kill their partners should not be able to manipulate and control their children from behind bars, which is why we are fixing the law to protect families from this appalling behaviour."

Under the proposed law, the courts would still consider the best interests of the child through a rapid and robust review stage and a right to apply to have the suspension lifted. And there will be an exemption for those parents who lash out with diminished responsibility following a history of domestic abuse.

The measures will be introduced to parliament as part of the Victims and Prisoners Bill.

Marsh was sentenced to life imprisonment for Ms Ward's murder in April 2022.

Labour's Shadow Justice Secretary, Shabana Mahmood, said: "We welcome the decision of the government to adopt Jade's Law, after what has been a difficult and agonising process for many families with years of tireless campaigning.

"This decision, however, has taken far too long. When we see cases of grave injustice, which cause immense trauma for families, the government has a responsibility to respond more quickly to right these wrongs."

Meanwhile, the government is expected to confirm that the legal expectation placed on judges to hand down whole life orders - except in extremely limited circumstances - will apply retrospectively to those who have already committed the worst crimes but are yet to be sentenced.

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In August the prime minister announced whole-life prison sentences will become the "default" punishment for "sexual or sadistic" murders in the wake of Lucy Letby's conviction for murdering seven babies and trying to kill six others.

Mr Sunak will say: "The public rightly believe that the most despicable killers should face life behind bars. That's why we are ensuring life means life for the most serious cases without the chance of parole.

"Today, we are announcing that we will extend whole life orders to those who have committed the crime but have not yet been sentenced so that more of the most vicious criminals face the punishment they deserve with no hope of ever walking free."