The four UK Unionist Assembly members embroiled in a dispute with party leader Mr Robert McCartney said they will not attend the emergency party meeting scheduled for next Tuesday.
Mr Cedric Wilson, the deputy party leader, publicly challenged Mr McCartney in Stormont on Tuesday to withdraw comments he alleged were made by Mr McCartney at a party meeting in November which "impugned" the character of the Assembly members. Mr Wilson said anything decided at the meeting next week would be "invalid in their eyes".
Mr Wilson said that Tuesday's meeting was not valid as the decision to hold the meeting had not been taken by the party executive and no formal agenda had been arranged. The UKUP Assembly members intend to hold their own meeting in early January to discuss the difficulties that exist between themselves and Mr McCartney.
Mr McCartney claimed his colleagues broke an understanding that in the event of meaningful cross-Border bodies being created, or Sinn Fein gaining ministerial positions, all five UKUP members would resign from the Assembly.