In a survey of its membership, the IMA found that certainty and counterparty risk have become the most relevant factors in the provision of best execution following the collapse of Lehmans.

Guy Sears, director, wholesale at IMA says: "Counterparty risk and settlement certainty dominates the selection process of brokers and venues following the settlement debacle arising in London from the Lehman collapse."

However, the competitive forces unleashed by the introduction of MiFID last year has led to a fragmentation of liqudity and subsequent deteriororation in the quality of information available to the buy side as multiple new marketplaces vie for business across Europe.

The IMA is calling for the creation of a central data repository, modelled on the US consolidated tape system, and the introduction of an order routing rule for European equity venues similar to Reg NMS in the US.

Says Sears: "The survey findings show that as far as UK equities are concerned, IMA members clearly think that the information quality has significantly deteriorated. Members would welcome the introduction of a rule for order routing similar to Reg NMS in the US."