Brevan Howard, the UK hedge fund manager, is set to raise €500m ($660m) less than it originally hoped with the flotation of its flagship fund on the London Stock Exchange, according to market sources.

The salesforce at Brevan Howard's bookrunners, Citigroup, Goldman Sachs and JP Morgan Cazenove, this morning told investors they had gathered €500m of demand for the float and would raise a maximum of €800m.