Wales to get new powers over water, UK Government says
New powers relating to water will be devolved to the Welsh Government under changes to the Wales Bill.
Welsh Secretary Alun Cairns said he would scrap his ability to block some laws made in Wales about water.
He said the decision puts right a "long outstanding injustice" 50 years after the flooding of a Gwynedd village to create a reservoir to supply Liverpool.
The Welsh Government said it had called for the devolution of these powers "for some time", so welcomed the move.
In 1965, the village of Capel Celyn was flooded to create the Tryweryn reservoir to provide Liverpool with water, under a law passed in 1956.
Mr Cairns told BBC Radio's Good Morning Wales programme the changes settled an injustice "where Wales was failed".
"Every secretary of state up until now has ducked this tough issue whereby water within Wales and England is inter-related" he said, saying intervention powers over water legislation were maintained "from Ron Davies to Peter Hain".
Analysis by David Cornock, BBC Wales parliamentary correspondent
Why does it matter that the UK government will no longer be able to block some Welsh laws on water?
There is the symbolism.
Today, planning laws might stop another Tryweryn but water remains a sensitive political issue.
It is also significant that Whitehall - after bruising negotiations between the Wales Office and DEFRA - has agreed to give up its veto.
The changes will be made as amendments to the Wales Bill, which is being debated in the House of Lords on Tuesday.
The Welsh secretary's powers to intervene on water-related legislation will be replaced by a legal agreement between the Welsh and UK governments.
The Wales Office said it was too early to say exactly when that would be, but said there would be no cost to the taxpayer and no change in how customers in England and Wales receive their water.
Former Plaid Cymru leader Lord Wigley said: "Plaid has fought hard over many years to get a fair settlement for Wales regarding water and to ensure that never again can a Tryweryn-type issue arise.
"I look forward to seeing exactly what the government has to say on Tuesday."
The changes will take effect once a formal agreement between the UK and Welsh governments has been signed.
A Welsh Government spokesman said: "We look forward to receiving further details on this as soon as possible."
The decision follows pressure from the Welsh Government and from opposition politicians who believe the Wales Bill leaves too much power at Westminster.