Icap, the world's largest interdealer broker, which has three staff involved in the FBI investigation into foreign exchange market fraud, has raised half-year pre-tax profits 47% to £85.4m (€123m). It has also increased the dividend by 21% to 8.5p and unveiled a five-for-one share split.

The figures were boosted by acquisitions, booming government debt and increased popularity of corporate bonds.