One of the largest independent operators of 'dark pool' trading venues has reported a strong increase in activity during the first quarter, in the latest sign that institutional investors are beginning to return to the market.

Simon Ormrod, chief financial officer and chief operating officer at Liquidnet Europe, said: "The trading community has put the wider market uncertainty from the persisting eurozone crisis behind it, and we are seeing a significant increase in appetite for block trading so far in 2012."