Euronext, the merger between the stock exchanges in Paris, Amsterdam and Brussels, has expanded its influence among Europe's smaller stock exchanges by signing a cross-trading and cross-membership deal with Hex, the Finnish stock exchange.

The deal marks the third time in as many months that Euronext has linked up with one of the smaller exchanges in Europe. This month Euronext signed a cross-access agreement with the Luxembourg stock exchange, and in the summer announced a merger deal for the Lisbon stock exchange to become the fourth member exchange of Euronext.