Relations between the DUP and Sinn Fein have further deteriorated after Arlene Foster said that Michelle O'Neill's apology over scenes at Bobby Storey's funeral did not go far enough.
Stormont sources told the Belfast Telegraph that relationships between Sinn Fein and every other party in the Executive were now "seriously damaged" by the Deputy First Minister's continuing refusal to accept that her actions were wrong.
Monday's joint press conference by Mrs Foster and Mrs O'Neill on Covid-19 has been cancelled.
The Executive will still meet that morning. A DUP source said it was "essential that the normal work of government goes on during a public health crisis".
He said: "The Executive is due to discuss travel and wedding restrictions at Monday's meeting. But Arlene won't be doing the joint presser with Michelle in the afternoon. That would present major credibility problems. Given the flagrant breaches of coronavirus guidelines at the Storey funeral, how could the public take seriously what would be said?"
Mrs Foster said that Mrs O'Neill's apology on Friday "falls short" of what was needed.
The Deputy First Minister had failed to acknowledge her role in causing hurt to people who had lost loved ones to Covid-19, the First Minister said.
"There was no recognition of any wrongdoing or recognition that there was a problem, no recognition that the credibility of the Executive has been damaged," she added.
Mrs Foster said she regretted that Mrs O'Neill had not offered a full and frank apology and she said that had damaged relationships "right across the Executive".
She added: "I will be speaking to other party leaders about this issue and trying to move forward. It is important we try and rebuild the trust that has been lost.
"The Executive has tried to deliver messages in relation to public health guidance to try and keep our people safe and unfortunately the credibility of that messaging has been severely damaged over this past week."
Mrs O'Neill acknowledged the "considerable controversy" over her attendance at the funeral. She said it was "unfortunate" the matter had divided the Executive.
She again insisted that she had acted within the rules in respect of everything within her control, such as the size of the cortege and the numbers attending inside St Agnes' Church.
"I will never apologise for attending the funeral of my friend," she said.
But she added: "I am particularly concerned that grieving families, who have lost a loved one during the pandemic, had their heartache compounded by the necessary restrictions which were in place at that time."
Four of the five main parties at the Executive want Mrs O'Neill to step aside pending a PSNI and Assembly standards investigations into Tuesday's funeral scenes.
She and party colleagues have been accused of flouting the Covid-19 regulations and guidance they had helped to set.
SDLP leader Colum Eastwood said: "Michelle O'Neill's statement falls far short of what is required. A half apology if people were hurt is not an acceptance that attendance at the funeral, in the middle of a pandemic, when others were being asked to stay at home, was wrong.
"To then go on to speak about the need to prevent a second wave or clusters of infection demonstrates how detached from the seriousness of this that she has become."
Ulster Unionist leader Steve Aiken welcomed Mrs O'Neill's recognition of the hurt caused to ordinary bereaved families. But he said she failed to recognise the main problem.
"The Northern Ireland Executive set rules, guidelines and regulations that she, as Deputy First Minister of this country, flouted. That is not acceptable, and that is why we're still calling for her to resign or to step aside."