text: Coalition kept alive in ‘zombie form’ as DUP leader appoints acting first minister, but Westminster resists his call to suspend devolved institutions
  
  Northern Ireland has been plunged into its worst crisis in nearly a decade after the first minister, Peter Robinson, resigned from his post in the wake of the alleged involvement of the IRA in a Belfast killing.
  
  In a dramatic move that threatens to collapse the Northern Ireland assembly for the first time since 2007, Robinson warned that the continued existence of IRA structures had “pushed devolution to the brink”.
  
  But the first minister, who has faced intense pressure after the smaller Ulster Unionist party (UUP) pulled out its sole minister from the executive, stepped back from pushing power sharing and devolution over the brink.
  
  Robinson appointed the finance minister, Arlene Foster, as acting first minister – a move aimed at keeping devolution going for a few more weeks – after failing to persuade David Cameron to suspend the Stormont assembly in Belfast. He emphasised that he had not “technically resigned”. Downing Street said the prime minister was “gravely concerned” by the events in Northern Ireland.
  
  The move, which also saw all the Democratic Unionist party ministers resign from the power-sharing executive, leaves a seven-day window for the British and Irish governments to try to patch together a deal between the DUP and Sinn Féin. Robinson has seven days to renominate his ministers. Elections to the assembly would be triggered if Robinson fails to nominate a new team.
  
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  The DUP leader wanted Cameron to take on powers that would allow him to suspend devolution for a short time in an echo of the repeated suspensions which eventually led to the resignation of Lord Trimble as first minister in 2002.
  
  The suspensions, which were ordered during a a lengthy row over the decommissioning of IRA weapons, undermined Trimble’s position and paved the way for the DUP, then the more hardline unionist party, to displace the Ulster Unionists as Northern Ireland’s largest party.
  
  In a reversal of roles, the much diminished UUP, which governed Northern Ireland from its creation in the 1920s until the imposition of direct rule from London at the height of the Troubles in 1972, is now putting pressure on the DUP over power sharing with Sinn Féin.
  
  Downing Street and the Northern Ireland secretary, Theresa Villiers, indicated that Westminster would resist pressure from Robinson, saying on Thursday night that she would not suspend the devolved institutions. Villiers acknowledged that the DUP resignations meant the functioning of the executive would become much more difficult. “It is a sign of a complete breakdown in working relationships within the executive,” she said.
  
  A No 10 spokesman said: “While acknowledging the gravity of the situation, the prime minister told Mr Robinson that the UK government did not believe it would be right to introduce emergency legislation now to suspend the assembly.”
  
  But Downing Street said that the prime minister had discussed with Robinson options “to comprehensively address all remaining paramilitary activity in Northern Ireland”.
  
  Facebook Twitter Pinterest Sinn Féin’s Martin McGuinness and Gerry Adams confer before speaking to the press on Thursday. Photograph: Charles McQuillan/Getty Images
  
  The prime minister encouraged Northern Ireland’s political parties to show leadership in emergency talks aimed at defusing the crisis caused by the declaration by George Hamilton, the chief constable of the Police Service of Northern Ireland (PSNI), that IRA members werebehind the murder of former comrade Kevin McGuigan last month.
  
  Robinson pointed to the arrest of Sinn Féin’s northern chairman, Bobby Storey, in connection with the McGuigan murder as a key reason why unionists had lost faith in sharing power with republicans. Storey and two other Belfast republicans have now been released without charge after being questioned over the McGuigan killing. Storey’s solicitor said he would be suing the police for unlawful arrest.
  
  Defending his decision to appoint Foster as acting first minister, Robinson said he had put her in the post to prevent political rivals making “irrational financial decisions”. “The failure of the SDLP and Sinn Féin to implement the Stormont House agreement, together with the assessment of the chief constable of the involvement of the IRA in murder, the continued existence of IRA structures, and the arrests that followed, has pushed devolution to the brink,” Robinson said.
  
  Keeping Foster inside the executive as acting first minister and finance minister keeps devolved government alive in “zombie form” and buys the talks process about six weeks, a DUP source told the Guardian.
  
  It is understood Robinson took action that stopped short of fully crashing the devolved institutions because he did not get Downing Street’s backing for suspension.
  
  But hardline Traditional Unionist Voice leader, Jim Allister, accused Robinson and the DUP of a U-turn on their threats on Wednesday that they would all resign from the executive.
  
  Earlier on Thursday, the SDLP resisted pressure from Ireland’s prime minister during a meeting in Dublin in which the taoiseach, Enda Kenny, urged the northern nationalist party to support adjournment as a means of saving devolution in Northern Ireland. The DUP later lost a vote to have business at the Stormont parliament adjourned.
  
  The SDLP leader, Alasdair McDonnell, said: “Adjournment would not have added anything, an adjournment would have been there and when the adjournment was over we would still have been drifting toward suspension. The adjournment was not the solution and we looked at this long and hard.”
  
  
  
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  McDonnell’s line meant it was inevitable that the DUP would act in relation with most of its ministers leaving the regional government.
  
  Sinn Féin said the DUP’s move was a “grave mistake”. The party’s president, Gerry Adams, said Sinn Féin were up for “real talks” with unionists and others. Adams said it was up to the PSNI and not politicians to investigate the McGuigan murder and the previous killing of ex-IRA man Gerard “Jock” Davison.
  
  McGuigan’s family and other republican sources have insisted since the father of nine was shot dead outside his home in East Belfast in August that the IRA was responsible.
  
  The Sinn Féin leader warned against intervention by Cameron leading to suspension. “I hope both governments support the integrity of these institutions and make it clear they will not suspend the institutions,” he said.
  
  Ireland’s foreign minister, Charles Flanagan, urged all leaders in Northern Ireland to “take a step back” and consider the gains achieved over recent years. Flanagan and Villiers are expected to be on call this weekend to resume talks between the parties aimed at rebuilding trust within the political process.
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  