
In what the Cameron-led coalition is calling the "largest public engagement project ever launched by the British government", the so-called who actively use Facebook.
In the two minute 52 second clip, the British prime minister thanks the 26-year-old digital specialist six times for his help with the project, and adds: "I’m really excited… It wouldn't be possible without you Mark."
Cameron, who earlier this month instructed government departments to prepare provisional plans for 40% budget cuts, was keen to stress the "millions of pounds if not billions of pounds" worth of cost-savings gained from the partnership.
Cameron said: "With your help we're basically getting this public engagement for free."
In his opening address the prime minister provides a sombre snapshot of the UK economy.
He said: "Basically we’ve got a big problem here. We need to save a huge amount of money. We've got the biggest budget deficit anywhere in the G20.
"This year we're borrowing more than almost any other European country – and the idea of using a social networking site to help harness people’s idea about how we save money, how we get value for money, and how we meet this huge challenge, I think is a great one."
The Spending Challenge will launch on the Democracy UK Facebook page by linking Facebook users to microsites specially tailored to focus on key issues open for discussion and debate among the voting public.
From the Democracy UK Page, people can navigate to Her Majesty’s Government website, where they'll find information which will help people to contribute informed opinions and actionable ideas.
The Democracy UK Page was Facebook’s home for discussion during the 2010 General Election campaign, with more than a million people participating in Election Day polls.