The letter, and some comments from Horsham's chair are below:
Letter from David Miliband to the County Times:
Through the pages of the West Sussex County Times I would like to thank the members of Horsham for nominating me as next leader of the Labour party.
Winning back the voters that Labour lost won't be easy. Labour has to change, to listen and to become the change that Britain needs.
We start this process by electing someone who is ready to face David Cameron at Prime Minister's Questions and stand as a credible alternative Prime Minister at the next election. That is why I am standing - to win for Labour.
I am honoured to have the support of Horsham party memebrs in my campaign. I promise I won;t let you down and that together we will rebuild our party and win for our values.
Local party members have had their say, in a few days millions of party members and members of trade unions will be asked to decide on who should be Labour's leader. I would urge all West Sussex County Times readers to use their vote and to visit www.davidmilliband.net to join the debateon Britain's future.
In response David Hide, chair of Horsham Labour party said:
Horsham Labour party are proud to have played an active role in the election of our new leader and very much appreciate David Miliband taking the time out to write and thank us for our nomination.
The election of our new leader goes to the heart of our party democracy and while David Miliband received Horsham Labour party's endorsement, all members and trade unionists now have the opportunity to vote for any one of the five excellent candidates. I would urge all our members to take part.
Whoever is elected, Horsham Labour party will be 100% behind our new leader and we will continue to provide the electorate with a credible alternative to the local Lib Dems and Tories. We will stand up for more affordable housing and oppose closures to our popular day centres, youth clubs and other vital public services.