The plan, which opens on January 1, 2008, offers investors the choice of a six-year option linked to the DJ Euro Stoxx 50 index or a five-year option linked to the FTSE 100. The six-year option offers investors 10 times the first 10% rise in the DJ Euro Stoxx 50 – an industry record multiple and maximum return requirement to double money.

The five-year option offers five times the first 15% rise in the FTSE 100, up to a maximum return of 75%. Both plans will return to investors their full capital unless their respective index falls by more than 50% and fails to recover to the starting point by maturity, in which case capital is lost 1:1 with the index performance. Returns are taxed as capital gains, allowing investors to use their annual CGT exemption. This treatment frees investors to use their ISA allowance for a different investment.

Colin Dickie, director of Barclays Wealth, said: We have an established track record with this style of product and they have always proved very popular with investors. However, we expect demand for this issue to surpass anything we have seen before as favourable pricing conditions have enabled us to offer a record multiple of 10 times the first 10% rise in the Euro Stoxx index.