Conservatives lose boundary review vote
29 January 2013 Last updated at 16:30 GMT
Liberal Democrat MPs have voted against their Conservative coalition partners for the first time to defeat a proposal to redraw constituency boundaries before 2015.
MPs voted by 334 to 292 to accept changes made by peers, meaning the planned constituency shake-up will be postponed until 2018 at the earliest.
The two coalition parties have been in dispute since proposed elections to the House of Lords were dropped last year.