With bankers unpopular over their bonuses and the financial services sector widely blamed for dragging Britain into a recession that has destroyed hundreds of thousands of jobs, both parties want to be seen as champions of manufacturing.

"I want us to be a country that stops just borrowing and buying from China and instead really starts selling to China," Cameron was due to say on Tuesday, according to remarks released in advance by his party.

The comment was in response to a new report on how to develop high-tech industries in Britain, commissioned by Cameron from James Dyson, inventor of a bagless vacuum cleaner that is a design icon and one of Britain's most successful exports.

The report, entitled "Ingenious Britain", says a cultural change is needed to draw more talent to science and engineering.

Dyson suggests a major national engineering prize and says the government should commit to French-style "grands projets", or long-term investments like high-speed rail and nuclear power.

France has had enduring success with its TGV high-speed rail network, which was launched in the 1980s and now stretches to almost every part of the country. Britain has only recently opened its first 68 miles of high-speed rail.

The Conservatives had already said they backed a high-speed rail link between Britain's major cities. Labour is also in favour and a government-commissioned study on a link from London to Scotland is due out by the end of this month.

Whichever party wins the election will struggle to find the necessary funding for big projects, given the fast-growing national debt. Both parties have pledged to cut the deficit, though they disagree about exactly when to start.

In his report, Dyson also advocated a government-guaranteed scheme to encourage banks to lend to innovative businesses, as well as refocusing research and development tax credits on high-tech companies and new start-ups.

"The current system is well-intentioned but not well targeted," he said, according to the Conservative release.

Dyson also suggested setting up industry scholarships for engineers in which the costs of bursaries to students would be shared between industry and government, and giving universities greater freedom to develop shorter or more vocational courses. (Reporting by Estelle Shirbon; editing by Robin Pomeroy)