An investigation into hundreds of car breakdowns across Britain last year has narrowed the cause to diesel from three storage terminals in northeast England, the British Standard Institute said.

However, an industry task force set up by the BSI earlier this year found no evidence that the filter-blocking incidents were caused by Russian diesel or additives, as initially suspected.

The BSI said it will introduce in the autumn mandatory screening of diesel for "filter blocking tendency." Such screening has helped to reduce the number of incidents.

Hundreds of diesel-fuelled cars broke down late last year, mainly in northeast England and Scotland, when gel-like substance blocked their engine filters. Vehicle-recovery services and the refining industry suspected fuel-quality issues related to cold weather.

Members of the UK Petroleum Industry Association, Essar, Esso, Shell, Phillipps 66, Total and Valero - began voluntarily screening for filter-blocking after the incidents.

It was unclear if the introduction of the mandatory test would lead to an increase in diesel prices.

Britain imported nearly half of the more than 10 million tonnes of diesel consumed last year, according to UKPIA data.