MINISTERS have been warned it will be "very dangerous" if plans to cut the number of MPs by 50 leads to constituencies spanning the historic boundaries between Yorkshire and Lancashire.
The Government's plans to cut the size of the House of Commons and make all constituencies about the same size have inflamed local passions across the country because the new arrangements may not be able to respect county boundaries.
Labour's Baroness Farrington of Ribbleton, a former Lancashire councillor, raised the legacy of the Wars of the Roses to stress the impact of having a cross-Pennines seat under the new system.
"It would be very dangerous to go to the dividing line between Lancashire and Yorkshire and start interfering with the boundary," she warned.
"There are parts of the dividing line between Lancashire and Yorkshire where people insist on having both the red and the white rose, because they still have not finished the War of the Roses."
Under the Parliamentary Voting System and Constituencies Bill, Ministers want to see the number of MPs reduced to 600 and constituencies reshaped so they are roughly the same size.
But while at the moment constituencies do not cross historic county boundaries, that will not necessarily be the case after seats are re-drawn by the Boundary Commission.
The Bill has been passed by the House of Commons but is currently in the House of Lords where Labour peers are accused of desperately trying to hold it up, leading to a bizarre all-night sitting on Monday night.
They are unhappy that the same Bill authorises a referendum on changing the voting system which is due to be held on May 5. Labour says the two issues should be dealt with separately.
Deputy Prime Minister Nick Clegg is a key supporter of reforms, although the shake-up of constituencies – which could see the number of seats in Yorkshire and Humber cut by about five – has raised concerns of being chaotic.
Even David Cameron has been dragged into the row over the decision not to respect historic boundaries after being lobbied intensively by campaigners in Devon and Cornwall opposed to the creation of a "Devonwall" seat.
After being inadvertently recorded making unguarded comments playing down the issue last year, he said: "The point I was making about political representation is I want to make sure we have equal-size seats right across the country.
"I don't see why we shouldn't cross county boundaries – even if they are quite historic boundaries – because that is the way you ensure you have proper representation for everyone."
The idea of cutting the number of MPs to cut the cost of politics was contained in the Tory manifesto, but there have been complaints that the decision to reduce seats from 650 to 600 is an arbitrary figure.