The Orange Order has formally cut its links with the Ulster Unionist Party, ending 100 years of historical ties.
The Order has been linked to the party for 100 years
The decision was taken at a meeting of the Grand Lodge in east Belfast.
The Order said because of restructuring within the Ulster Unionist Party, it would have to make "impracticable changes" to its constitution.
Orange Order Grand Master Robert Saulters said the arrangements made 100 years ago were no longer relevant in the political scene today.
Speaking after the meeting, he said: "The loyal Orange Institution will continue to lobby for the unionist cause as
"We will seek to establish good relationships with all those engaged in the political interests of the unionist people."
The links between the Ulster Unionists and the Orange Order dated back to a time when there was only one unionist party, but many Orangemen now support the DUP.
The UUP had refused to sever its ties, though the Order's influence had been greatly reduced in recent years.
Ulster Unionist MLA and Orangeman Jim Rodgers said the Order's influence had reduced to the point where many brethren felt unwelcome.
Speaking ahead of Saturday's decision, he said: "Speaking to Orange brethren, they have said they have felt most uncomfortable for some considerable time within our party.
"It seemed to be like a cold house to them."
Fellow Ulster Unionist Sir Reg Empey said he was sure the two organisations would remain close.
"I think we have to keep focused on what continues to bind us together - support for the union (and) that is the same, whether you're in the Orange institution or not," he said.
BBC Northern Ireland political correspondent Gareth Gordon said such a move was once unthinkable, but it said much about the shift within unionism that the decision was to be made with "little more than a whimper".