Northern Ireland's main pro-Agreement parties have been trying to break the political deadlock in the wake of the IRA's proposal to put its arms beyond use.
After talks with senior colleagues on Tuesday, Mr Trimble called for actual decommissioning to begin as soon as possible.
Mr Trimble said: "We have seen a step by republicans, but of course, it falls far short of what we need - which is to see decommissioning actually begin."
'Positive nature'
Mr Trimble said there had been no developments of "a positive nature" since Monday.
He said the governments' paper was not going to be attractive to unionists without the necessary steps on decommissioning by republicans.
Meanwhile, the nationalist SDLP gave a positive assessment of proposals by the British and Irish Governments to save the Good Friday Agreement.
Although party leader John Hume described the proposals as "positive", he said a number of concerns remained, not least the failure of the government to publish the implementation plan on policing reform.
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Mr Hume said: "There are still some matters of concern but there is no doubt we have made work in that direction."
But the SDLP's stance was criticised by Mr Trimble.
'Deeply disappointing'
Mr Trimble said the SDLP response on policing was "deeply disappointing".
He said it was "wholly inadequate" and "not a way in which a serious political party should behave".
Both governments reacted positively to the IRA proposals, announced on Monday, to put its weapons beyond use after it was made to the international decommissioning body.
A statement from the commission, headed by General John de Chastelain, gave no details of the suggested method, or of any timetable.
But the general said the proposal met with the commission's remit in accordance with the UK legislation on the scheme and regulations.
Arms body meeting
Later on Tuesday Mr Trimble led a delegation to meet General de Chastelain to discuss the method which had been proposed by the IRA for decommissioning.
The Northern Ireland secretary on Tuesday announced that he had signed an order to approve a new decommissioning scheme, which comes under the current decommissioning legislation.
Mr Trimble said the party was unhappy because "when we met General de Chastelain on Friday, he didn't see fit to tell us that he had asked for a new scheme or that a new scheme had been made on Thursday and came into effect on Friday".
Earlier, the Sinn Fein Minister, Martin McGuinness, said Mr Trimble's rejection of Monday's decommissioning report was a mistake of "huge proportions".
Midnight deadline
He said: "What I want to see now is everybody in this process recognise that the person that needs to be put into the driving seat to deal with the issue of arms is the international body under General de Chastelain."
The UK government has said it would allow "more time" for decisions, after all of Northern Ireland's major parties failed to react to the 10-page "Way Forward" document by the deadline of 0000BST on Monday.
The current political crisis in Northern Ireland was precipitated by the resignation of Mr Trimble as Northern Ireland first minister on 1 July because the IRA had not begun to disarm.
If the plan is rejected, it would plunge the future of the Good Friday Agreement into uncertainty, and would entail either suspending the Northern Ireland Assembly or calling new elections.