Tories to gain just three seats from boundary changes Tories lose out on big poll gains from boundary changes

The Conservatives are estimated to make an effective gain of just three seats from boundary changes being laid before Parliament today - far fewer than early predictions of up to 20.

Against early expectations, the new constituency boundaries, redrawn to take account of the move of population from Labour inner cities to Tory suburbs, will have hardly any effect on the next general election. The main impact may be to threaten the safe seats of a number of ministers.

The Boundary Commissioners have added eight seats, to take the House of Commons from 651 MPs to 659, with five more seats in England, two in Wales and one in Northern Ireland.

The results of a study commissioned by the BBC, ITN, PA News and Sky News suggests that had the 1992 election taken place using the new boundaries, the Conservatives would have won 343 seats (up 7), Labour 273 (up 2) and the Liberal Democrats 18 (down 2).

The Conservative majority would have been 27 instead of 21 - the equivalent of transferring just three seats from the Opposition to the Government.

The study, carried out by Dr Colin Rallings and Dr Michael Thrasher of Plymouth University, says Labour now needs a swing of 0.8 per cent from the Conservatives to deprive them of their majority, hardly more than the 0.5 per cent swing needed on the old boundaries.

Changes for Scotland and Wales have already been approved by Parliament. The changes for England are being laid before Parliament today, and those for Northern Ireland are also expected to be approved before Parliament rises for the summer.

Ministers who may look for a new seat because of the changes include: Brian Mawhinney, Secretary of State for Transport, whose marginal Peterborough seat becomes slightly safer, is expected to try for the new ultra-safe Tory seat of Cambridgeshire NW; Stephen Dorrell, Secretary of State for National Heritage, whose Loughborough seat becomes marginal, may try for the adjacent new safe Tory seat of Charnwood; Sir George Young, Financial Secretary to the Treasury (Ealing Acton); Sir John Wheeler, Minister of State for Northern Ireland (Westminster N); James Arbuthnot, Social Security minister (Wanstead and Woodford); Sir Paul Beresford, Environment minister (Croydon Central) faces a challenge for the new Croydon seat from David Congdon (Croydon NE). The Chelsea constituency of Sir Nicholas Scott, the former minister who is on police bail after a car accident in which a toddler was hurt, is merged with Kensington.

Labour casualties include John Fraser (Norwood), who has already been beaten by Tessa Jowell (Dulwich) for a new south London seat, and Bryan Davies, an education spokesman, loses his Oldham Central and Royton seat.