Vale of Glamorgan Council has backed calls for the Crown Estate to be devolved in Wales.
16 of the 22 Welsh local councils have now come out in favour of calls for profits to be reinvested here - a view shared by the Welsh Labour Government, but not by the UK Labour Government.
Following a debate on Monday night, a Plaid Cymru motion backing devolution was passed by 39 votes to twelve.
In Wales, the Crown Estate controls around 50,000 acres of land and owns around 65% of the Welsh coastline and riverbeds along with the seabed up to 12 miles out to sea.
According to campaigners, the value of such assets stood at around £850 million two years ago and may have since risen to over £1 billion.
At the moment, the money goes to the Treasury before being spent across the UK - although the Scottish Government has control over the Crown Estate in Scotland.
Plaid Cymru councillor Mark Hooper, who led the party's motion, said it was "anachronistic" for the funds to be "channelled to the King".
The Baruc ward councillor said: "This motion mattered. Whilst this council’s payments to the Crown Estate runs into the hundreds of pounds per year, rather than other local authorities who pay many thousands, this motion mattered to residents who care about this issue and it mattered more broadly to Wales in general as our nation is again the subject of being under-powered by Westminster."
He added: "This outdated position is unsustainable in a modern Wales and needs to change. After all, the Crown Estate is devolved to Scotland, so we have a model that works."
"I’m pleased that councillors from across the chamber supported the motion on Monday. It's now up to Labour in the UK Government to listen to the clear message from the Vale, and 15 other local authorities across Wales."
"Welsh Labour MPs have voted against devolution of these assets only recently, whilst their party colleagues in local government and the Senedd stand ready to take on the profitable national assets. This position isn’t sustainable, and we look forward to change in the UK Government’s position very soon."
Fifteen other councils have supported similar calls over the past six months, including Swansea, Rhondda Cynon Taf and Merthyr Tydfil.
Two years ago, a YouGov poll found that 75% of those who responded also backed transferring control of the Crown Estate in Wales.
Pro-independence group YesCymru, which is planning to stage a march in Barry next month, says the amount of money flowing out of Wales and into the Estate has become "an urgent issue" as councils face severe financial pressures.
Speaking ahead of its AGM in Powys last weekend, YesCymru chair Phyl Griffiths, said: "Local authorities across Wales are stepping up and demanding what is rightfully ours – the ability to control our own natural resources for the benefit of our communities. Westminster has ignored these calls for too long, despite the fact that Scotland has already been given this power."
"We are talking about £853 million in Welsh wealth, much of it from offshore renewables, that could be reinvested in Wales instead of being siphoned off to London. This isn't just about money; it's about fairness and self-determination."
But last month, Treasury minister James Murray told MPs that devolving the estates to Wales would make "no commercial sense" and "further fragment" the UK-wide energy market, saying that devolution would need a "new entity" to manage the Crown Estate in Wales.
He added it would not make sense in terms of increasing net profits which are reinvested into public services "right across the country, right across Wales and other parts of the UK".
Earlier this week, Welsh Secretary of State, Jo Stevens, warned devolution would put the potential for thousands of wind power jobs at risk of "market fragmentation" or "potentially destroying developer confidence".
Meanwhile, a former Welsh Conservative leader claimed Vale Council's vote on devolving the Crown Estates would be seen as "out of touch" by local residents.
South Wales Central MS Andrew RT Davies said: "It's not the business of the Vale Council to call for further devolution, which most people in Wales are against anyway."
"But, more importantly, in all my years of politics, I've never knocked a door and been told by someone that their priority is the devolution of the Crown Estate."
"Likewise, in all my years of helping constituents, I've never been unable to help somebody as a result of the constitutional status of Crown Estate assets."
"The council should spend less time on these fringe issues and more time working to set a lower council tax rate so hardworking Vale residents can stop being used as cash cows."

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