By Nina Chestney

LONDON, Sept 7 (Reuters) - NYSE Euronext and environmentalmarkets infrastructure provider APX Inc. will create a jointventure, NYSE Blue, to develop global environmental markets, thecompanies said on Tuesday.

"The intention is to create other exchanges in other partsof the market. NYSE Blue will operate as one single companyaround the world and the trading infrastructure will be linked,"Brian Storms, who will become NYSE Blue's chief executive whenthe deal is cleared, told Reuters in an interview.

NYSE Blue will focus on environmental commodities related tocarbon emissions and renewable energy trading but it also seespotential for new types of trading around energy efficiency andwater.

Storms, who is currently the chairman and CEO of APX, wouldnot comment on the value of the joint venture.

NYSE Euronext shares in Paris rose 0.76 percent to 23.20euros at 1429 GMT.

U.S.-based financial markets operator NYSE Euronext saidearlier it would contribute its 60 percent shareholding inFrench emissions exchange BlueNext and be the majority owner ofNYSE Blue.

Shareholders in APX Inc., including Goldman Sachs,MissionPoint Capital Partners and ONSET Ventures will take aminority stake in NYSE Blue in return for their shares in APX.

NYSE Blue will try to attract "important and strategic"investors into the new company, Storms said.

It will offer services such as pre-trade and post-tradeplatforms, environmental registry services, markets referencedata and the BlueNext spot emissions platform.

The companies expect the transaction to close by the end ofthis year, subject to shareholder and regulatory approval.

EXPANSION

Storms said environmental markets will grow in North Americaand Asia, even though legislation for a federal U.S.cap-and-trade scheme and global climate pact talks have stalled.

"We are very mindful of the pace environmental markets aredeveloping," said Storms.

"This is a critical marketplace. Over time, policies will berationalised and we want be in a position to help influencethose outcomes and be a major participant when they do develop,"Storms said.

Privately-owned APX Inc. provides infrastructure forenvironmental commodities and energy markets. It has a strongpresence in the U.S. renewable energy certificate market and theglobal voluntary carbon market.

APX may change its name eventually, but its current serviceswill continue under the new joint venture, Storms said.

NYSE EuroNext has a 60 percent stake in Paris-basedBlueNext, while French state-owned bank Caisse des Depots holdsthe remaining 40 percent.

BlueNext is the main marketplace for spot trading inEuropean Union carbon permits under the bloc's $100 billionemissions trading scheme.

"BlueNext will continue to intensely focus on its corebusiness in Europe," Storms said.

He denied that the joint venture was formed in response toNYSE's main U.S. rival Nasdax OMX's purchase of Nordic powerexchange Nord Pool ASA in March.

"It was a reaction to the market, not an individualcompetitor. We believe the two companies will enjoy competitiveadvantages which they wouldn't have enjoyed separately." (Reporting by Nina Chestney; editing by Anthony Barker)