Four in 10 UK business owners have more confidence in their prospects than they did three months ago, a new study finds.

The growing sense of optimism motivated all companies surveyed by Alliance & Leicester Commercial Bank to pledge more investment in their business during the coming three months. However, most of this investment is expected in the manufacturing sector.

Nearly half of all business owners surveyed said they expect the country's economic prospects to remain unchanged over the next quarter.

Meanwhile, nearly eight of 10 respondents reported business performance either in line with or better than their expectations. Only one in 10 business owners reported they are less confident about the future.

"At a time when a general election is anticipated and there is uncertainty over interest rate rises, it is encouraging to see so many businesses planning growth," said Alex Smith, senior product manager at Alliance & Leicester.

All three major parties pushed their plans for boosting business confidence in manifestos published this week as the opening shots were fired in the run-up to the general election on May 5.

Labour, predictably, has campaigned on the strength of its economy - for example the country's low interest rates, which have remained at 4.75% for the eight consecutive months.

The Liberal Democrats and the Tories, meanwhile, have promised to cut regulation and maintain the economy's stability, while keeping interest rates low. Both have set their sights on the Department of Trade & Industry, with the Liberal Democrats calling for the department's abolition.