* Euronext says will pay in cash
* Merger proposal follows acquisition of Dublin bourse (Adds CEO comments, background, share price)
By Noor Zainab Hussain and Julien Ponthus
LONDON, Dec 24 (Reuters) - Pan-European exchanges group Euronext NV is set to add the Oslo bourse to its portfolio after winning the support of shareholders owning almost half of the Norwegian stock exchange for a 625 million euros ($711 million) bid.
Euronext, which already operates bourses in Paris, Amsterdam, Brussels, Lisbon and Dublin, has offered to buy Oslo Bors for 145 Norwegian crowns ($16.58) per share, a 20.8 percent premium to the Norwegian firm's last traded price on Friday.
Euronext CEO Stephane Boujnah said the opportunity for a deal emerged about six weeks ago when a group of Oslo Bors shareholders organised an auction for their stake.
After winning the auction, and with it the support of shareholders representing 49.6 percent of outstanding shares, Euronext approached the board of Oslo Bors VPS to seek their backing for an agreed takeover.
Oslo Bors said its board would give shareholders its view on the offer once it had been presented.
Boujnah said Euronext did not need to raise debt or capital to finance the deal.
"We will not need to go to the market, we will use our cash," he told Reuters, adding Euronext had long standing contacts and interest in the Oslo exchange, viewing it as a "natural partner".
Shares in Paris-listed Euronext were down 0.13 percent at 47.38 euros as of 1135 GMT.
While Euronext aims to build a diversified pan-European group of stock markets, opportunities are scarce, either because operators already belong to industry heavyweights such as London Stock Exchange and Nasdaq Inc, or because their shareholders want to remain independent.
Mega-mergers have also been met with opposition from competition regulators who blocked a planned tie-up between Deutsche Boerse and the London Stock Exchange.
The deal matches both Euronext's strategy of bolt-on acquisitions and its desire to diversify its revenues from share trading, with Oslo Bors' position in seafood derivatives as well as oil services and shipping.
Its listings are dominated by companies in the oil sector such as Equinor and Aker BP, oil services firms such as Aker Solutions, Subsea 7 and Kvaerner, as well as fish farmers such as Marine Harvest, the world’s largest, and Leroy Seafood.
On the risk posed to financial markets should Britain leave the European Union without a negotiated framework, Boujnah said Euronext took the matter seriously.
"We hope for the best, prepare for the worst", he said, adding that "considering where we are, less than one hundred days before Brexit, it seems that the possibility of a no-deal Brexit is high".
Additional reporting by Gwladys Fouche in Oslo; Editing by Mark Potter and Huw Jones