The research company forecasts that digital budgets will become 20 per cent of the total, accounting for about $50bn (£31bn) worldwide.

It predicts the momentum of digital disruption will continue to grow across all verticals in 2013 – such as healthcare providers being challenged by personal tracking devices, broadcasters threatened by the likes of YouTube and banking platforms competing with new services such as Square.

Forrester’s “Trends for the B2C CMO to watch in 2013” report warns these disruptors threaten to challenge all businesses if marketers do not expand the utility and value of the experience their brands deliver.

The report, compiled by Forrester’s CMO and market leadership professionals analyst Corinne Munchbach, advises CMOs to work across departments and with executive peers to assess their digital readiness and identify where messages, actions and products can be improved by digital.

Munchbach advises marketers to use surplus budget at the end of the fiscal year or tie funding for new projects to positive business results to ensure their companies commit funding to innovation projects.

Budget should also be reorganised out of channel silos and into new cross-platform teams organised around consumer segments, with experts on the relevant media, channels and devices for that particular vertical, Muchbach says.

The report also advises marketers to maintain a shared “centre of excellence” for broader campaigns to help achieve scale for overlapping initiatives and to establish a multifunctional group from the marketing, R&D, IT and operations divisions to track how digital elevates their parts of the business to improve the brand experience for consumers.

In the UK, online and mobile ad spend increased 13 per cent to £2.6bn in the first half of 2012, according to the IAB and PwCs advertising expenditure report.