Lawyers for the families of victims of the Omagh bombing are today threatening to sue Sinn Fein president Mr Gerry Adams for slander.
The families are angered at Mr Adams' claim that there is an ulterior motive for their issuing to him a subpoena as part of a £10 million compensation action against those alleged to have committed the atrocity.
Mr Adams and four other senior republicans, including MPs Mr Martin McGuinness and Mr Pat Doherty, have been ordered to appear at the Northern Ireland High Court by legal representatives of some of the families of the 29 people killed in the Real IRA blast in August 1998.
The families claim the five were members of the IRA's army council at the time of the resignation the previous year of quartermaster general Mr Michael McKevitt, who allegedly went to head the Real IRA when Omagh was hit.
Mr Adams said he had no evidence to offer the families and suggested there was an ulterior motive to him being subpoenaed along with Mr Doherty, Mr McGuinness, Mr Brian Gillian and Mr Brian Keenan.
The civil action against Mr McKevitt and four other dissident republicans is due to go ahead later this year.
Lawyers and trustees for the relatives claimed the subpoena against the Sinn Fein president was issued after careful consideration and followed extensive inquiries which established a reasonable belief he could provide relevant evidence to the court.
A statement added: "To suggest that the subpoena was issued for an ulterior purpose or to serve any agenda, save that of the legal interests of the plaintiffs, is a slander against the professional standards and duties of the lawyers and trustees who act on behalf of the families.
"If Mr Adams repeats such a slander publicly, we will be obliged to consider legal action."
PA