Aberdeen's Labour group will remain suspended until the next election in 2022, the party has said.
Nine Aberdeen City councillors were suspended in 2017 after they disobeyed former leader Kezia Dugdale's instructions not to form a coalition with the Conservatives.
The coalition came about after the last local government election.
The group were referred to the party's national constitutional committee to have their membership considered.
Scottish Labour leader Richard Leonard said the decision sent out a clear message that "serious rule breaches will result in serious repercussions".
"It is disappointing that the nine councillors in three and a half years have offered neither regret nor a resolution to avoid this decision," he added.
"I have expressed my frustration before that this case has taken so long to be brought to a conclusion. Now it is time to move on."
But Jenny Laing, the leader of suspended group, said it was "deeply disappointing" the three and a half year long suspension was to continue, particularly as the councillors were found not to have breached party rules.
Cllr Laing, who is also co-leader of the council with Conservative colleague Douglas Lumsden, added: "The Aberdeen Labour Group remain determined to deliver for the people of Aberdeen, to deliver the Labour manifesto on which we were elected and to stand up to the SNP government on the city's behalf at this critical time.
"We will not be distracted from those tasks by internal party matters."
The council is currently led by a coalition of independent, Conservative and suspended Labour councillors.