The family of Pat Finucane have described the Government's decision not to hold an immediate public inquiry into his murder as an "absolute insult".
The 39-year-old solicitor, who represented republican and loyalist paramilitaries during the Troubles, was shot dead in his family home in north Belfast in February 1989 by the Ulster Defence Association, in an attack found to have involved collusion with the state.
Mr Finucane's widow Geraldine and the couple's three children have been campaigning for decades for a public inquiry to establish the extent of security force involvement.
Northern Ireland Secretary Brandon Lewis said he met the Finucane family on Monday to inform them of the Government's decision, before announcing it in the House of Commons.
He says PSNI and Police Ombudsman investigations into the 1989 shooting are to go ahead.
WATCH: Geraldine Finucane speaks to UTV Live:
Geraldine Finucane told UTV she was "absolutely devastated by the arrogance of the Government in making this decision".
She said: "We have campaigned for 31 years and ended up in the UK's Supreme Court, where they said that no investigation that had taken place up until that time had been effective.
"That included at least two police investigations - so what did the secretary of state say to me and the family? 'Oh let's have another police investigation'.
"It was an insult, an absolute insult, and I made my feelings about this very clear to the secretary of state, that the responsibility for the Government was to announce a public inquiry and they just ignored their own courts."
The secretary of state told MPs in Parliament he is "not taking the possibility of a public inquiry off the table at this stage".
He added that the PSNI and police ombudsman processes must move forward without the risk of prejudicing any emerging conclusions from their work.
Mr Lewis said: “The murder of Patrick Finucane was an appalling crime that has caused tremendous suffering.
"The UK Government is clear that the shocking levels of collusion in this case are totally unacceptable, and has publicly apologised that this took place.
“This case is sadly but one example of the violence and tragedy experienced by so many individuals and families during the Troubles, not just in Northern Ireland but across the United Kingdom and Ireland.
"It demonstrates the importance of ensuring that all families affected by the Troubles have an opportunity to find out the circumstances of their loved one’s death.
“We remain committed to working collaboratively with the Irish Government, the Northern Ireland parties, and civic society, including victims groups, in finding and delivering a progressive way forward on legacy to support NI in working towards a more positive future."
Last year, the Supreme Court said all previous examinations of the death had not been compliant with human rights standards.
The court acknowledged Ms Finucane had been given an "unequivocal undertaking" by the Government following the 2001 Weston Park agreement with the Irish Government that there would be a public inquiry into the murder.
The judges found that the Government had been justified in later deciding against holding one.
The court said it was up to the Government to decide what form of investigation was now required, if one was feasible.
Amid a Government delay in responding to the judgment, Ms Finucane took fresh judicial review proceedings against the state.
In a statement on Monday, PSNI Chief Constable Simon Byrne said: "It is our view that there are currently no new lines of inquiry.
"We now need to decide if a further review is merited given all the previous investigations into this case.
"Once we have determined that, we will inform the Finucane family. If we determine that a review should take place, we will then have to decide if we are best placed to carry out that review."
Politicians have also been reacting to the announcement.
Simon Coveney, the Irish minister for foreign affairs, said: “It has been the strong and consistent position of the Irish Government that only a full and independent public inquiry, as provided for under the Weston Park agreement in 2001, would provide a satisfactory outcome to this case.
"We are disappointed that the opportunity was not taken today to establish such an inquiry without further delay.
"However, we note that the secretary of state has not ruled out the holding of such an inquiry."
SDLP Leader Colum Eastwood said Brandon Lewis had "failed miserably" to do right by the family of Pat Finucane.
He added: "Does he realise that he is sending out a very clear message to all victims and the message is this - if you want the truth about what happened to your loved ones, don't come looking for it here."
DUP Commons Leader Sir Jeffrey Donaldson called for a "holistic approach" to legacy that enables all innocent victims to have access to truth and justice.
He explained: "What we really need is not some special attention to any one case, but a holistic approach to legacy that enables all innocent victims to have access to truth and justice."
Sinn Féin's Michelle O'Neill said: “The British government has again shown that they have no regard or respect for the families of those killed by state collusion.
“The decision not to hold a public inquiry has wider implications for legacy matters and the implementation of the Stormont House Agreement.
“I want to pay tribute to the courage, bravery and resilience of Geraldine Finucane and her family. They have spoken truth to power.
“I, and Sinn Féin, will continue to support them in the campaign for a full public inquiry."
The UUP's Doug Beattie said: “What we must do now is establish and agree a legacy process which is fair, balanced, equitable and proportionate.
"We need a process which can deliver closure for as many families as possible.
"And for the avoidance of doubt, as far as the Ulster Unionist Party is concerned, that process cannot be the legacy arrangements of the Stormont House Agreement."
Alliance MP Stephen Farry said: "This is a very poor decision.
"It comes on top of the side-lining of the Stormont House Agreement which is the key to a comprehensive approach for all victims.
"But the Finucane case in particular raises serious questions regarding the rule of law, actions of the State and accountability.
"I do strongly support the PSNI, but this approach is turning back the clock in terms of investigations."