"Disclosure of those documents would have undermined the protection of the public interest so far as concerns the economic policy of the European Union and Greece," the court ruled on Thursday.

The ruling, in a case brought by news agency Bloomberg News, can be appealed on points of law only to the EU's highest court, the European Court of Justice, within the next two months.

Bloomberg News asked the ECB in August 2010 to disclose two documents entitled "The impact on government deficit and debt from off-market swaps. The Greek case" and "The Titlos transaction and possible existence of similar transactions impacting on the euro area government debt or deficit levels".

The ECB refused access to the documents. Bloomberg News challenged that decision in the General Court.

"In today's judgment, the General Court dismisses that action," the court said in a statement.

The judges agreed with the ECB that it could not disclose the first document because the information it contained was outdated, posing a substantial risk of severely misleading the public in general and financial markets in particular.

"In a very vulnerable market environment, that disclosure would affect the proper functioning of the financial markets. Thus, disclosure of the information contained in that document would undermine public confidence as regards the effective conduct of economic policy in the EU and Greece," the statement said.

The court also found that the content of the second document was closely connected with the first, and that the ECB had not made a mistake in assessing that its disclosure too "would undermine the economic policy of the EU and Greece".

Privately-held Bloomberg competes with Thomson Reuters (TRI.N), Dow Jones & Co, a unit of News Corp (NWSA.O), and other news and data providers.

(Reporting by Jan Strupczewski; editing by Rex Merrifield)

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