The IICD says it believes the UDA will decommission by February
The international body set up to oversee decommissioning in Northern Ireland has said it expects the UDA to decommission its arms by February 2010.
In its latest report, the Independent International Commission on Decommissioning (IICD) also confirmed the UVF had completed decommissioning.
But UDA leader Jackie McDonald warned recent dissident republican activity was making loyalists nervous.
He highlighted last month's incident of a road-block by gunmen in south Armagh.
"When the PSNI have to tiptoe away from a situation where dissident republicans are openly having road-blocks there is great concern within loyalist working class communities and within loyalist paramilitaries as well," he said.
"So they haven't gone away yet you know."
In June, the organisation and associate group, the Red Hand Commando, said they had destroyed their weapons.
NI Secretary Shaun Woodward said the report was "hugely significant".
No loyalist arms division
From BBC NI home affairs correspondent Vincent Kearney
There's been much speculation in recent weeks about a split within the UDA over decommissioning.
The organisation decommissioned a small quantity of weapons in June, and it's been claimed that move led to serious divisions.
But the international commission says it met members of all five of the mainstream UDA's so-called brigades last week.
It was told there's no difference of opinion and that the organisation will complete the process of decommissioning before the end of February.
The commission says the break-away South East Antrim "brigade" has also decommissioned some weapons, and given a commitment to complete the process within six months.
"Northern Ireland has been transformed over the past decade and the work of General John de Chastelain and the IICD has helped society to move away from conflict and towards peace," he said.
"The end is in sight for the decommissioning process.
"So much has been achieved by the IICD since it was established and I would urge all groups to continue to work with the Commission and put their arms beyond use before the scheme comes to an end in February."
In the report, General de Chastelain, from Canada, and fellow commission members Norwegian Brigadier Tauno Nieminen and Andrew Sens, from the United States, confirmed they had witnessed the UVF/RHC decommissioning acts at first hand.
A substantial quantity of firearms, ammunition and explosives were put beyond use, they said.
The commissioners also said they were given assurances from the mainstream UDA's five so-called "brigades" and the South East Antrim grouping that they would complete their decommissioning by the end of the IICD's mandate in February.
They also dismissed recent speculation that the UDA's Londonderry/North Antrim "brigade" was refusing to give up its arms and said its leaders had given a commitment they were still on board.
"In conclusion, we feel that substantial practical progress has been made on decommissioning loyalist paramilitary arms," they wrote.
The UDA decommissioned a small quantity of weapons in June, but in recent weeks there has been speculation about splits within the organisation over the issue.
However, the IICD report said that it had met all the mainstream UDA's "brigades" and was told there was no difference of opinion.
Earlier this year, Mr Woodward warned that legislation, which set a deadline of February 2010 for the completion of decommissioning, would not be renewed.