Mr David Trimble is expected to be on the Tory conference platform this morning to hear the British Prime Minister, Mr Blair, accused of "betraying the trust" of the people of Northern Ireland.
The hardline critique of Mr Blair's handling of the peace process will come from the shadow secretary of state, Mr Andrew Mackay, prior to a short debate on Northern Ireland.
Mr Mackay will reject complaints from Mr Blair and Dr Mo Mowlam that the Conservatives have endangered the bipartisan policy, and increased Mr Trimble's difficulties, and tell the conference bi-partisanship does not mean "a blank cheque" for government.
In a speech supporting Mr Trimble's continuing refusal to form an executive with Sinn Fein, and making more explicit Conservative hostility to key recommendations in the Patten report on the future of the RUC, Mr Mackay will say: "It is our constitutional duty as an opposition to speak out when we believe Tony Blair is making mistakes, and neither William Hague nor I shall be deterred from continuing to do that."
Mr Mackay will repeat previous criticisms of Mr Blair's failure to suspend prisoner releases pending a start of paramilitary decommissioning, and for failing to uphold the pledges he gave in the run-up to last year's referendum on the Belfast Agreement.
"Regrettably, Tony Blair said one thing and has done another. He has betrayed the trust of the people of Northern Ireland."
He will also say that continuing terrorist violence is "incompatible with the complete and unequivocal ceasefire required before prisoners can be released, and representatives of terrorist groups can be admitted to government".
He will tell the conference that was why Conservatives supported Mr Trimble in July "when he refused to be bounced into forming an executive with members of Sinn Fein", and that "it is simply wrong in a democracy to ask constitutional politicians to sit in government with representatives of fully armed terrorist organisations".
Affirming Conservative support for the implementation of all aspects of the agreement, Mr Mackay will endorse Mr Trimble's proposal that Ulster Unionists and Sinn Fein should move simultaneously, "setting up the executive at the same time as decommissioning begins".
"But only if there is a clear, transparent timetable for decommissioning and a legally binding guarantee that if the IRA fails to deliver, the government will seek Sinn Fein's exclusion from the executive."
Mr Mackay sees "no justification" for changing the name and cap badge of the RUC, and will warn that "it would be dangerous folly for Tony Blair to implement changes that affect security until there has been a complete end to violence and the decommissioning of terrorist weapons".
Mr Trimble, who will not address the conference proper, is scheduled to address a Unionist Information Office event at lunchtime, before Mr Hague's closing address. Mr Trimble delivered the prestigious Swinton Lecture last night at the conference centre on the theme of post-devolution Britain.