A UUP delegation will travel to Dublin today to brief politicians at Leinster House, as it appeared certain a united unionist Assembly motion to exclude Sinn FΘin will be debated soon.
An Ulster Unionist spokesman yesterday said he expected an exclusion motion to be debated within the next fortnight.
The announcement follows discussions between the UUP leader, Mr David Trimble, and the DUP leader, the Rev Ian Paisley, on Tuesday.
A UUP representative for north Belfast, Mr Fred Cobain, a member of the delegation, said democratic parties must stand together on the issue.
"It is very important that politicians in Dublin and the local media understand the depth of concern within the community in Northern Ireland about the ongoing refusal of the IRA and other terrorists to end their activities and begin decommissioning," Mr Cobain said.
The DUP has attempted to table its own exclusion motion since the Assembly's return following the summer recess but has fallen one short of the 30 signatures necessary for it to be debated.
Earlier this week, UUP attempts to secure signatures of members of the anti-agreement Northern Ireland Unionist party were thwarted when the party leader, Mr Cedric Wilson, refused to sign if Mr Trimble would not table it immediately.
Mr Trimble has threatened to withdraw UUP ministers from the Executive if the motion fails, which it will do without cross-community support from the SDLP. In any joint motion all unionist MLAs, except the PUP, will be invited to sign. The debate is expected on October 10th.
Mr Alex Maskey, of Sinn FΘin, last night repeated his party's warning that the move would force the collapse of the political institutions.
He said Mr Trimble was closing down the possibility of progress on outstanding issues. "It is a powerfully negative message that David Trimble is sending to nationalists and republicans that he is now happy to collude with every anti-agreement faction in the Assembly," Mr Maskey said.