High-tech company Oxonica says it needs to raise more funds, following the re-listing of its shares on the London Stock Exchange.

The shares had been suspended since April 27, after it lost a key contract with Turkish state oil company Petrol Ofisi.

Trials had failed to show any definite savings when Oxonica's fuel additive Envirox was added to high-sulphur diesel.

New trials will now start with low-sulphur diesel, which will become the main lorry fuel in Turkey from July 2008, and which is being used successfully by Stagecoach buses in the UK.

Oxonica made 13 people redundant at its headquarters at Begbroke Science Park, near Kidlington, when it lost the contract and now has less than 30 staff.

It has £2.6m cash reserves and says the cost-cutting means its annual spending has reduced from £900,000 to £650,000.

However, it said a financial review was expected to show that the company would need to raise funds in the next few months with a share offer.