In a first-quarter update the group said sales growth of 28 per cent excluding precious metals had been helped by new emission standards for diesel vehicles in Europe and North America which boosted demand for catalysts.

The Swindon fuel cell fact- ory, employing nearly 100 people, is set to recruit more staff to cope with orders for membrane electrode assemblies (MEAs) for fuel cells such as those used in motor homes.

MEAs are still in their infancy but are expected to find wide use in consumer electronics, local power generation and later in vehicles.

The Swindon plant is the group's sole MEA factory.

Johnson Matthey said pre- tax profits rose 12 per cent in the three months to June 30 with sales up nine per cent.

However, its shares fell on worries of a delay in US approval for the prostate cancer pill satraplatin, from which it is due to receive royalties.

Shares closed at GBP17.46, down 3.1 per cent or 56p.