NYSE Euronext Inc. has entered the competition for the Borsa Italiana by submitting a preliminary bid to rival the London Stock Exchange Group's offer, according to the online edition of the Wall Street Journal.

NYSE Euronext's offer is around 1.5 billion euros, or about $2 billion, as is the LSE's, the Journal said, quoting people familiar with the matter.

The NYSE Euronext offer is at a preliminary stage and could be restructured, according to the report. NYSE Euronext is the parent of the New York Stock Exchange. It could not immediately be reached for comment.

The LSE said on Wednesday it has begun discussions with the Milan bourse and a source told Reuters the talks were at an advanced stage.

Also on Wednesday, Borsa Italiana exercised an option to buy Euronext's stake in MBE Holding, which controls European bond trading platform MTS. By buying full control of MTS, Borsa Italiana would bring an international asset to an agreement with the LSE.