Ulster Unionist leader Mr Trimble tonight wrote to more than 800 members of the party ruling council with a personal appeal for support.
He goes before a meeting of the Ulster Unionist Council in Belfast on Saturday which has been called by hardliners not satisfied with the start to the IRA's decommissioning of weapons.
In a pre-emptive strike ahead of the meeting, he sent out the `trust me' letter in a bid to stop the council tying his hands with a deadline by which they say decommissioning must be completed or he walks out of government again.
At the same time the Northern Ireland First Minister said at a Belfast news conference the pro-Belfast Agreement parties should meet together to set a target date for the full implementation of the Agreement, including decommissioning.
Mr Trimble said he had not forgotten about decommissioning and would keep the pressure on.
He said he planned to issue a progress report to the UUC in March next year.
"I think I have demonstrated that I am persistent on this issue, that I have taken things right down to the line - and beyond - and that I am clearly focused on what it is necessary to achieve.
"I am asking them, we having succeeded so far, to leave the detail and the tactics to me and my colleagues for the future."
He said he wanted the council to give him a "resounding level of support" on Saturday "so we can go forward into the New Year with confidence focused on our objectives and on meeting the concerns of the unionist community".
Proposing the pro-Agreement parties take up a suggestion from the SDLP that they have roundtable talks to set a new target date for the full implementation of the Agreement - including decommissioning, he said "We haven't got a time frame for decommissioning and we need one."
PA