US presidential candidate John McCain has pledged a $300m reward for the development of a better battery-powered car.

The Republican presidential hopeful said that, if elected, he would post the reward to the first manufacturer that develops a car which is able to alleviate America's dependency on oil.

"Whether it takes a meeting with automakers during my first month in office, or my signature on an act of Congress, we will meet the goal of a swift conversion of American vehicles away from oil," McCain told a crowd in Fresno, California.

The move comes as US petrol prices continue to soar. The average price for a gallon of petrol is now $4.08, and the economy has continually been cited as one of the top issues in the upcoming election.

The proposal also pushes McCain further into the traditional Democratic strongholds of green technology and reduced oil consumption.

Last month, McCain bucked GOP tradition when he included carbon caps in his environmental policy.

McCain trails Democratic candidate Barack Obama in a number of national polls, but has enjoyed strong support from the IT community.

A March survey by the Computer Technology Industry Association placed the two candidates in a dead heat among IT professionals.

The UK has announced a low-carbon initiative of its own which encourages companies to collaborate on green vehicles.