Whole-life tariffs are "wholly justified in the most heinous cases", the Government has said, as it further negotiates with European human rights judges over a controversial ruling against the so-called "life means life" terms.
Whole-life terms were deemed a breach of human rights following a successful appeal to the European Court of Human Rights (ECHR) by murderers Jeremy Bamber, Douglas Vinter and Peter Moore.
Ministers have sent an initial response to the Council of Europe, which oversees the ECHR, to confirm it is considering what steps are necessary as a result of the judgment.
But the Ministry of Justice added the Government intends to argue whole-life tariffs should remain available to courts when a number of key cases are brought before the Court of Appeal later this month.
Lee Newell, who murdered child killer Subhan Anwar in prison, and murderer and rapist Matthew Thomas are to challenge their whole-life terms on January 24. April Jones murderer Mark Bridger was understood to be challenging his whole-life term but this is yet to be confirmed by the courts.
In addition, the Attorney General has referred the case of Ian McLoughlin, who was given a life sentence with a determinate tariff of 40 years for murdering a man on day release.
In each case, the central legal issue is the nature of the sentencing scheme for whole life orders and the compatibility of such an order with the European Convention on Human Rights.
A Ministry of Justice spokeswoman said: "The Government has today responded to the Council of Europe, noting the Court's judgment.
"We are clear that this raises important issues, on which Parliament and the public has strong views, and that our response should not be rushed.
"The Government remains firmly of the view that whole life tariffs are wholly justified in the most heinous cases, and that they should continue to be available to the courts.
"We will be strenuously arguing in the Court of Appeal that a judge can and must impose a whole life order in cases such as these."
Some 52 criminals are serving whole-life sentences including Ian Brady, the Moors murderer and serial killer Rosemary West.
Last year's appeal by Bamber, Vinter and Moore ruled that their whole life sentences amount to ''inhuman and degrading treatment''.
Whole-lifers should be entitled to a review of their sentence 25 years into their term at the very latest, the Grand Chamber of the Strasbourg-based court said.
The ruling by 17 judges from across Europe sparked further outrage among critics of the court - despite reassurances that the decision did not amount to grounds for imminent release.
Five judges will consider the test cases - all involving multiple murders - at the Court of Appeal later this month.
One of the test cases concerns triple killer McLoughlin, 55, who was jailed for life at the Old Bailey last October for stabbing a man on his first day-release from prison after 21 years in custody.
When sentencing McLoughlin the trial judge imposed a 40-year tariff, saying he could not pass a whole-life term because of the European court ruling.
McLoughlin - who had killed twice before - stabbed Graham Buck, 66, as he came to the aid of a neighbour in Little Gaddesden, Hertfordshire, last July.
Attorney General Dominic Grieve referred his case to the appeal court because he regards McLoughlin's sentence with the 40-year minimum term as "unduly lenient".
In a second case, Newell, 44, is challenging a whole-life sentence imposed last September at Warwick Crown Court.
He was convicted alongside Gary Smith for the February 2013 murder of convicted child killer Anwar in his cell at Long Lartin Prison, Worcestershire. Newell was already serving a life sentence for a previous murder committed in 1988.
And in a third case, convicted rapist Thomas was told "life means life" after murdering a newlywed bride and then kidnapping and raping a second woman.
Thomas, then 43, from Luton, pleaded guilty to the murder of Colette Magee in Luton in November 2013. He also admitted two counts of rape, one of indecent assault and one count of kidnap of the second woman.