The additional funds are expected to be available from 2015-16. However, business and industry observers questioned whether the boost was sufficient and warned that past budget pledges on infrastructure failed to materialise into projects.

Osborne said in parliament that the government was "already supporting the largest investment in railways since Victorian times and spending more on new roads than in a generation".

Nick Prior, head of infrastructure and capital projects at Deloitte said: "While the GBP 3bn (USD 4.5bn) is welcome, there is no indication at all of where it’s going to be spent. Given the track record over the last three years of delivering against commitments, one has to be extremely cautious about the impact this will have. There has been a lot of rhetoric over infrastructure spend over the last three years, but delivery has fallen well short of the promises."