Cameron announced at the Conservative Party Conference yesterday that the scheme allowing people across the UK to take out 95 per cent mortgages would be launched next week – three months earlier than planned.
He rejected concerns raised by Business Secretary Vince Cable and others that the move could lead to a housing boom.
Westbourne director James Bethell said the Government should clearly communicate its vision of what the scheme would achieve.
"Voters understand that many people these days struggle to find the money for a deposit and therefore can never hope to own their own home," he said. "This is an injustice that voters understand the Government is right to address. However, they rightly fear that a Government loan scheme could bring about another housing bubble, with memories of 110pc mortgages still raw. The key objective for the Treasury is to make clear the distinction between a leg-up for hard workers and a dangerous bubble."
Cameron's announcement follows Labour leader Ed Miliband's pledge at his party conference last week to freeze energy bills for 20 months if Labour wins the 2015 general election.
Interel managing partner George McGregor said: "Despite being some 20 months away from the general election, both parties are now engaged in a retail war where they are offering transactional policies that will have a material outcome on the lives of voters.
"In many ways the move shows that Miliband has had some success in moving the terms of the debate away from the economy and on to standards of living but Labour will have problems if the policy proves a success."
He added Cameron’s move was a positive one because it demonstrated action rather than words, but risky considering claims from within the coalition that the policy might overheat the housing market and lead to a recovery based on debt.
Westminster Advisers managing director Dominic Church added that bringing forward the scheme in the middle of a debate about a housing bubble could be seen as slightly panicked response to Miliband’s speech, but the move was playing well with voters.
"It is polling well, just as Miliband’s energy price freeze is polling well, especially in marginal seats, so you can see why they’ve made these announcements," he said. "But both of them could be accused of early electioneering."