It could be the ultimate line in luxury clothing - garments spun from spider silk.

Scientists have revealed they can generate the fine but strong threads used by spiders to make their webs by growing it in genetically modified tobacco plants.

They have developed a method of purifying the silk from the plants and then spinning it into long threads several metres long.

Scientists have revealed they can generate the fine but strong threads used by spiders to make their webs by growing it in genetically modified tobacco plants.

Unlike traditional silk from silkworms, the threads used in spiders’ webs cannot be farmed on a mass scale as the arachnids are highly territorial and tend to attack each other if kept in close quarters.

Fashion designers have previously attempted to make clothing from spider silk, but it can take years to gather enough to weave a length of cloth.

The new technique, however, raises the prospect of being able to grow and collect spider silk from plants in much the same way as common textile materials like cotton.

The scientists at Clemson University in South Carolina who developed the technique say it could allow large quantities of spider silk to be produced for use in clothing.

It promises a new generation of lightweight but hardwearing clothes as spider silk can be up to five times stronger than steel weight for weight. It is also stronger than kevlar so could also be used in protective clothing.

Professor Bill Marcotte, chair of genetics and biochemistry at Clemson University in South Carolina who led the research, said it may be possible to produce clothes using silk from the plants within a few years.

He said: ‘We were able to pull fibres several metres long but we are currently limited as all fibres are pulled by hand.

‘We are trying to develop a mechanism to semi-automate fibre pulling, but those efforts are underway. These fibres could potentially be used in textiles.’

The researchers, whose work is published in the journal Biomacromolecules, introduced genes from the golden orb web spider Nephila clavipes into tobacco plants.

This allowed the plants to produce two large proteins called Major ampullate Spidroin 1 and Major ampullate Spidroin 2 - the main components of the orb web spider’s dragline silk.

Draglines are used by the spider to build the main outer parts of a web and are the strongest of the different silks it produces. This silk lacks the sticky coating that captures prey on webs.

In the natural world, spiders produce the proteins in silk glands as a liquid, which turns into fibres due to changes in acidity in their silk ducts before being pulled out of pairs of tiny spinnarets.

The researchers tried to mimic this by purifying the silk proteins from the tobacco plants and treating them with an acid and a chemical called glutaraldehyde - disinfectant normally used for treating warts.

This caused the silk proteins to form a thin film over a gum. The researchers could then pull this film into thin fibres.

These were left to dry in the air before being soaked in water - similar to a process that happens in the natural world when dew forms on webs - causing the silk strands to become narrow and stronger.

Professor Marcotte said they were able to produce fibres that were only a fraction of the strength of natural silk.

He said: ‘Our fibres do not come even close to rivaling natural silks.’

They are not the only researchers trying to create artificial silk.

Earlier this year scientists in Sweden demonstrated they could create silk fibres up to a mile long by growing proteins in bacteria and pumping it through extremely fine glass tubes.

Researchers at Utah State University also managed to produce silk proteins in the milk of genetically modified goats. The goats produce about an ounce of silk in their milk, which is then purified and spun into fibres.

The process, however, was still too expensive to make spider silk commercially available and a company set up to produce it from the goats went out of business.

It is hoped that by growing them on tobacco plants - which are already a cheap and easily grown crop - it may make production more affordable.

Professor Marcotte said the silk proteins could also be used to create gels for use in medical dressing.