ICE will look at selling Euronext, NYSE's European stock market business, in an initial public offering after the deal closes in the second half of next year.
"Our transaction is responsive to the evolution of market infrastructure today and offers a range of growth opportunities," ICE chairman and CEO Jeff Sprecher said in a statement.
ICE will buy NYSE, which also owns derivatives market Liffe, for $33.12 per share in stock and cash, a 37 per cent premium to its Wednesday closing price and valuing NYSE Euronext at $8.2 billion.
NYSE Euronext shares rose nearly 32 per cent after the deal was announced, while ICE's shares fell four per cent.
Analysts said the deal will give Atlanta-based ICE a strategic boost with control of Liffe, Europe's second-largest derivatives market, helping it compete against U.S.-based CME Group Inc, owner of the Chicago Board of Trade.
"ICE is after Liffe, that is the crown jewel of NYSE Euronext," said Peter Lenardos, analyst at RBC Capital Markets.
"Strategically it makes sense for ICE to enter the European derivatives space in a meaningful way."
ICE, founded in 2000, has its roots in electronic commodity trading and a tie-up with Liffe will boost trade for soft commodities such as sugar, buoying its profits.
"I would imagine that, having the softs contracts under one roof, would provide for easier arbitrage, financing and development of trading opportunities behind the contracts, via swaps and options," said Jonathan Kingsman, a sugar trade veteran who heads agriculture at information provider Platts.
"If you have clearing membership of ICE, you could trade London contracts under the same membership."
An ICE-NYSE Euronext tie-up would leap-frog Deutsche Boerse to become the world's third-largest exchange group with a combined market value of $15.2 billion. CME Group, ICE's largest U.S.-based rival, has a market value of $17.5 billion, Thomson Reuters data shows.
Hong Kong Exchanges and Clearing is the world's largest exchange group with a market cap of $19.5 billion.
ICE's main operations are in energy futures trading and unlike NYSE Euronext, it has steered clear of stocks and stock-options trading, so there is not much business overlap between the two groups, making it more likely competition authorities would approve a tie-up, analysts said.
Last year, the US Justice Department blocked a $11 billion joint hostile bid by ICE and Nasdaq OMX Group for NYSE Euronext on concerns the tie-up would dominate U.S. stock listings.
If that bid had succeeded, ICE planned to buy NYSE Euronext derivatives business while Nasdaq would have taken control of the stock exchanges.
A rival $9.3 billion bid by German exchange operator Deutsche Boerse also fell foul of regulators.
"I doubt the competition authorities will have a problem with it, there's only a modest overlap between the businesses," said Richard Perrott, an analyst at Berenberg Bank.
"The rationale for the deal will be the same as that with Deutsche Boerse - migrate the clearing of Liffe derivatives to ICE's services in London and scale up to attract OTC (Over The Counter) derivatives clearing."
ICE said it expected to achieve $450 million in cost savings from the deal.
Before the latest ICE offer emerged, NYSE Euronext's shares had fallen by nearly a third since ICE and Nasdaq launched their thwarted joint bid.
The New York Stock Exchange, known as the Big Board and the symbol of U.S. capitalism, has seen its clout fade as new technology and the rise of private trading venues run by Wall Street banks and brokers cut its margins.
ICE, which started out as an online marketplace for energy trading, is the product of a string of acquisitions from the London-based International Petroleum Exchange in 2001, to the New York Board of Trade and, most recently, a handful of smaller deals, including a climate exchange and a stake in a Brazilian clearing house.
Copyright @ Thomson Reuters 2012