The changes to the electoral map are being made to ensure constituent numbers are similar for each seat.

Credit: ITV News

ITV News Political Correspondent Romilly Weeks explains why the electoral map is changing, and what it could mean for the next election.

Why is the electoral map changing now?

Proposed new constituency boundaries have been published which could see the number of MPs in Wales reduced by a fifth.

Number of Welsh MPs to be cut from 40 to 32 under new proposals

The Commission has reduced the number of seats from 18 to 17.  Four new constituencies will be created and Belfast's four will remain.

In the proposed boundary changes to the South West, a new constituency will be created, crossing the border between Devon and Cornwall.

Welsh MPs will be cut from 40 to 29 under plans for a smaller House of Commons, with a similar number of voters in each constituency. 

The Boundary Commission for Wales has made major changes to its proposals for 30 Welsh seats at Westminster, to replace the existing 40. 