Pan-European exchanges group Euronext, which plans a bid to buy Oslo Bors, said it had now secured the backing of a majority of shareholders in the Norwegian stock market operator.
Euronext said shareholders representing 50.6% of the capital of Oslo Bors had agreed to sell their shares ahead of the tender offer that Paris-listed Euronext plans to launch in the coming weeks.
On Monday, Euronext had said shareholders representing 49.6% of Oslo Bors' capital backed its bid.
Euronext, which already operates bourses in Dublin, Paris, Amsterdam, Brussels and Lisbon has offered to buy Oslo Bors for €625m, a price that represents a 21% premium to the Norwegian firm's share price at the close of trade on December 21.
Euronext already owns a 5.1% stake in Oslo Bors but owning more than 10% would require approval from the Norwegian government, which may hinge on the contents of Euronext's upcoming offer document.
Oslo Bors, which is due to celebrate its 200th anniversary in 2019, will give its view on the offer when the bid has been formally presented, a spokesman said.
Euronext is seeking to build a diversified pan-European group of stock markets but opportunities in the region are scarce.
This is either because operators already belong to industry heavyweights - such as the London Stock Exchange and Nasdaq - or because shareholders want to remain independent.