Jeremy Corbyn has rebuffed the Scottish Labour leader’s call for a “new Act of Union”.
Kezia Dugdale proposed a federal structure for the UK last month in a bid to end the constitutional wrangling across the country and stave off the threat of independence.
The UK Labour leader took issue with the MSP’s choice of words in an interview with the BBC.
Mr Corbyn agreed with Ms Dugdale in saying there needs to be a convention to investigate alternative constitutional arrangements.
But he added: “I would not use the words new Act of Union.”
The Islington North MP also said there is no need for a second independence referendum and questioned whether the devolution of immigration powers to Holyrood is possible.
Mr Corbyn said: “There is a huge issue about regional government across England, and there is a need to have a discussion about the relative powers in Scotland, in Wales and in Northern Ireland of devolved assemblies.”
A spokesman for Scottish Labour said: “Kezia Dugdale has proposed a new Act of Union, to strengthen our union across the whole of the UK for generations to come.”