NYSE Euronext said on Thursday it would not join Deutsche Boerse in appealing the European Commission's decision to prohibit the $7.4 billion merger between the two exchange operators.

The deal would have created the world's largest exchange. European regulators argued it would have given the combined group a near monopoly in the worldwide market for European derivatives.

Frustrated by the ruling and how it defined the derivatives market, Deutsche Boerse said on Monday it was appealing to Europe's General Court, the lower chamber of the European Court of Justice.

NYSE said that while it believes the European Commission's decision was based on an incorrect market definition, it does not believe the interests of its shareholders and of the company itself would be served by getting involved in a protracted appeal.

We remain convinced of the original rationale for the proposed combination and the many benefits it would have created for the industry, our customers and the European economy, NYSE said in a statement.

However, as we said at the time of the prohibition, our sole focus has returned to executing our strategy and leveraging the significant opportunities we have to grow the business and continue to create long-term value for our shareholders, customers and employees.

Antitrust lawyers have said they see little chance of success in Deutsche Boerse's appeal and that it may be challenging the ruling only to ease the way for future deals.

(Reporting By John McCrank)