The British Business Bank has launched a £210mn investment fund for smaller companies in south-east England, extending its network of regional finance programmes as the government seeks to increase investment outside London.

The South East Investment Fund will provide loans ranging from £25,000 to £2mn and equity investments of up to £5mn to businesses across Buckinghamshire, Oxfordshire, Berkshire, Hampshire and the Isle of Wight, Sussex, Surrey and Kent.

The state-owned development bank said the programme was intended to address regional disparities in access to growth capital, particularly for innovative companies attempting to move from research and development into commercial expansion.

The South East is home to 17 per cent of UK university spinout companies, according to the bank, second only to London. However, businesses in the region attracted just 5 per cent of total UK equity investment by value last year.

The fund has made its first investment, providing a £250,000 loan to Process Vision, a Basingstoke-based technology company. The financing will support commercial growth and international expansion.

The FSE Group will manage the debt portion of the programme, while Maven Capital Partners will oversee its equity investments.

The launch comes ahead of a separate East of England Investment Fund due later this month. The British Business Bank said the two programmes meant it would offer targeted regional finance across every UK nation and region outside London.

David Hourican, incoming interim chief executive of the British Business Bank, said the South East contained some of the country's most innovative technology and science businesses but needed better access to finance.

"This fund will ensure that businesses have local access to the finance they need to grow, scale and expand," he said.

Business secretary Jonathan Reynolds said improving access to capital was central to the government's aim of generating growth across the country.

"We are determined not to let access to investment be a barrier to success for businesses in the South East," he said.

The fund forms part of the British Business Bank's wider effort to address geographical imbalances in UK small-business finance, with regional programmes designed to channel debt and equity capital towards companies that can struggle to attract investment from traditional sources.