NYSE Euronext and Deutsche Boerse said they have terminated their merger plans, following the decision by the European Commission to block the proposed deal.

The transaction that would have created the world's biggest stock exchange operator was cleared by U.S. regulators in December, but was rejected by European anti-trust authorities on Wednesday, making it the fourth among a series of large exchange deals to be blocked over the last year.

The $7.4 billion (4.6 billion pound) merger agreement between the two companies was announced nearly a year ago, but the European Commission blocked it saying that the combined entity's near-monopoly would make it hard for new players to compete.

NYSE Euronext shares were up marginally at $26.74 in morning trade on Thursday on the New York Stock Exchange.

(Reporting by Brenton Cordeiro in Bangalore; Editing by Sriraj Kalluvila)