Cyprus-based FxPro is one of the largest players in the retail FX trading market and has tens of thousands of UK clients. But the sector received an unexpected blow in December when the Financial Conduct Authority announced plans to cap the amount that retail investors can risk when using such services.

Sky News reports that FxPro has written to a number of prospective non-executive directors lined up for boardroom positions following the IPO to inform them that the company will remain in private hands for now.

FxPro is not the only retail trading platform to be unnerved by the FCA's move. UK-based derivatives dealing platform CMC Markets is considering a move to Germany where the banking regulator BaFin has also announced new measures for spread betting investors that are felt to be less draconian than the FCA's proposals.

Of particular concern to regulators is the trading of contracts for difference (CFD). Back in December the FCA said it had "serious concerns that an increasing number of retail clients are trading in CFD products without an adequate understanding of the risks involved, and as a result can incur rapid, large and unexpected losses".

A sample of CFD retail traders examined by the FCA found that 82% of them lost money on these products.

The FCA's proposals would include the use of standardised risk warnings and a cap on leverage to 50 times the original stake. Meanwhile the BaFin proposals aim to prevent traders losing more than their initial deposit but do not plan to limit either leverage or the marketing plans of spread betting companies.