SCOTLAND'S breakaway Labour-led councils have been dealt a major blow with one leader announcing his authority could split from the group.

Eddie McAvoy, leader of South Lanarkshire, said there "may be merit" in his authority rejoining the country's main local government body Cosla.

In a politically significant move and just days before the organisation's annual conference, the Labour veteran issued a joint public statement with Cosla's president, David O'Neill, praising it's recent changes on the back of an internal review.

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It followed a meeting between the pair at South Lanarkshire's Hamilton headquarters.

In the statement, Mr McAvoy praised progress made by the group of rebel councils, the Scottish Local Government Partnership (SLGP) and which also includes Glasgow, Aberdeen and Renfrewshire, in becoming a voice for their council areas.

But he added: "However, at the meeting I told Cllr O’Neill that if these changes to Cosla are progressed there may be merit in the council reconsidering its membership of Cosla, but that this would be a decision for the council following the election."

The blow comes at a crucial time for the SLGP, which has recently held meetings with local government minister Angela Constance over its quest to be given full negotiating status in financial dealings with the Scottish Government.

The Government has repeatedly stated that while it will hold discussions with the four authorities over key issues it will only negotiate with Cosla.

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The four authorities broke away in 2014 in a row over the Government's financial settlement and where power lay within Cosla, claiming the new group would have the freedom to negotiate a better deal on funding for council tax payers.

But since then, councils have been hit with around £500m in cuts, the harshest financial settlement in a generation. There has been speculation the group could fold in the event of significant SNP victories in next May's local elections, although it has also been suggested it could become a rallying point for Labour-led authorities.

One source said: "No matter the outcome of the election there is an acceptance that maybe South Lanarkshire needs to rethink its relationship with Cosla. If there's a change of administration its extremely likely an SNP-led council would rejoin.

"But even if there's a Labour-led administration they may view that the circumstances are right to come back on board with Cosla. There's not a lot of planning within South Lanarkshire regarding the SLGP beyond May."

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Mr O’Neill said: I had a very good meeting with Cllr McAvoy where I outlined in detail to him the direction of travel that Cosla is going to be taking.

“Tackling inequality has always been my real political passion and this remains the case. However now more than ever I believe that if we are to tackle the scourge of inequality that blights Scotland then we as local government stand a better chance of doing so with 32 Councils as opposed to 28.

SLGP convener, Jenny Laing, said: “Eddie McAvoy has confirmed that his own local authority remains committed to the SLGP and has rightly pointed out that the best interests of Aberdeen, Glasgow, Renfrewshire and South Lanarkshire are served by holding the Scottish Government to account on matters like funding, social care, housing and poverty, something we have rigorously pursued over the past 18 months.”