LABOUR is poised to unveil plans for "radical federalism" as an alternative to Scottish independence, the Sunday Herald has learned.

The politician charged with preparing Jeremy Corbyn's programme for government is to state his backing for a federal British state.

Shadow cabinet office minister Jon Trickett says the “emergence through time of a federal Britain" will be "stronger and fairer” for all parts of the UK.

In a flagship speech tomorrow, Trickett will give the strongest indication yet that a Labour government would deliver a radical shake-up of the constitution.

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Trickett was asked to examine plans for federalism in early 2017. However, his "constitutional convention" has come under growing pressure to state its position.

Scottish Labour leader Richard Leonard even said it should get a "move on" with its review. Leonard's remarks led to a row between the pro-independence and Unionist parties.

The SNP said "billions of years from now Labour politicians will no doubt be staring into the dying sun" considering federalism.

However, Trickett now says Labour must embrace “radical federalism”. The unexpected call will be made in a speech to the Institute for Public Policy Research tomorrow.

In exclusive extracts seen by the Sunday Herald, Trickett says Labour in power must end the UK’s “over centralised state”.

Trickett became convinced of federalism following accusations that the Tories sought to stir up anti-Scottish sentiment at the 2015 general election, it is understood.

The Tories ran aggressive campaigns in English constituencies that suggested Scots MPs would dominate a minority Labour government led by Ed Miliband, in the event of a hung parliament.

In the speech titled 'Transforming Politics in England', he will claim that Labour needs to convince English voters about federalism.

However, Trickett believes that a major reshaping of the British state would be popular in Scotland as an alternative to independence.

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Labour has already said it will set up a constitutional convention to examine federalism if it wins the next election.

Trickett will say: "In my view we'll end up with substantial regional devolution in England that in my mind will lead to the emergence through time of a federal Britain, which will be stronger and fairer as a consequence.

"Our over centralised state has failed to deliver a socially just country. We will need to have a deep conversation with people who quite honestly are sick of things been done to them rather than for them.

"Jeremy Corbyn has committed the party to the creation of a constitutional convention that will discuss the way forward, including the issue of a more federal Britain."

Under federalism, a series of regional and national parliaments and assemblies would be created across Britain, with a federal government retaining powers over foreign affairs, defence, currency, welfare and pensions.

However, independence campaigners challenged Labour to state exactly what powers would be devolved to Holyrood under its plans.

Gordon MacIntyre-Kemp, chief executive of the pro-independence think tank Business for Scotland, said Labour's approach was "flawed".

In a letter to Richard Leonard, Kemp said federalism would be vetoed by voters in other parts of the UK.

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Kemp said: "If you really believe in Federalism, as a Scottish party leader you owe it to Scottish people to actually say what you mean by Federalism and what powers you believe Scotland needs."

He added: "I would like to point out some flaws in the Federal idea ... There is simply not enough support for Federalism in England, where most voters live, and in Northern Ireland the DUP would feel it would diminish their status as British."

SNP MSP Linda Fabiani MSP added: “These are just more empty words from Labour who have promised a super-charged, powerhouse, federalism-max for years but have consistently failed to deliver it."