The Democratic Unionist Party was tonight accused of still playing "catch-up" on its Ulster Unionist rivals.
UUP leader Mr David Trimble claimed the DUP lacked a vision for Northern Ireland and risked allowing republicans "unpick" the Belfast Agreement.
The Upper Bann MP told Ulster Unionists in east Belfast that the DUP was "desperately hoping that they can exploit the difficulties and pains of the transition [from paramilitary activity to democratic power-sharing] in order to snatch the spoils of our successes".
"They no longer seek to destroy the Agreement ... Given a fig leaf of a 'renegotiation', they will cheerfully accept the places and power the Agreement gives to locally elected representatives.
"Their problem, however, is that they have never yet been able to accept responsibility, never yet been able to lead.
"They seek a renegotiation but have never successfully conducted a negotiation.
"They say they want changes but have produced no alternatives, no policies.
"They acknowledge that they will have to compromise but give no hint of what they will give and, in doing this, they run the risk of giving republicans the chance to unpick a constitutional settlement that copper-bottoms the Union.
"If the DUP had any capacity for self-awareness, they would acknowledge that they are still in catch-up mode."
Mr Trimble's attack on his main unionist rivals follows a series of rallies by the DUP accusing the Ulster Unionists of being out of touch with voters.
DUP deputy leader, Mr Peter Robinson, last night claimed in Coleraine the UUP was "in political free-fall".
However, Mr Trimble insisted that the Ulster Unionists had bolstered Northern Ireland's position within the United Kingdom.
PA