UK 5 July 2010 Tory backbenchers do not have a mandate to block the AV bill Bernard Jenkin and others better think hard before they move to strangle the key to the coalition. Sign UpGet the New Statesman's Morning Call email. Sign-up If it is true that Tory MPs such as Bernard Jenkin, among "many" others, are planning to vote down the Alternative Vote referendum bill announced by Nick Clegg in the House of Commons today, then they better think again. The Conservative Party did not, let it be repeated, win the election outright and the referendum plan is the glue that holds the coalition with the Liberal Democrats together. As the official coalition agreement states: The parties will bring forward a referendum bill on electoral reform, which includes provision for the introduction of the Alternative Vote in the event of a positive result in the referendum, as well as for the creation of fewer and more equal-sized constituencies. Both parties will whip their parliamentary parties in both houses to support a simple majority referendum on the Alternative Vote, without prejudice to the positions parties will take during such a referendum. Both parties will, as is made clear, be whipped. A rebellion against that could well bring down the fragile coalition and result in a general election. › Defeat for Kaczynski leaves Cameron isolated in Europe James Macintyre is political correspondent for the New Statesman. Subscribe For daily analysis & more political coverage from Westminster and beyond subscribe for just £1 per month!