According to sources familiar with the matter on Wednesday, OPEC has denied reporters from Reuters, Bloomberg, and The Wall Street Journal access to cover a meeting of oil sector CEOs with OPEC and its allies. A source stated that Reuters reporters received an email that they had no invitation to attend. Sources familiar with the matter confirmed that Bloomberg and WSJ reporters got a similar email.

OPEC emphasized in the email that the press participation was by invitation only and that prior accreditation - which OPEC referred to as "self-accreditation" - would not give access to the event.

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The three media companies are in competition for live coverage of events such as OPEC+ meetings, which may have a significant influence on the price of oil and the worldwide cost of energy.

Saudi Arabia and Russia are among the leading oil producers in the Organization of Petroleum Exporting Countries and its allies, known as OPEC+. OPEC+ is responsible for more than 40% of the world's oil output.

OPEC did not elaborate on why the organizations were denied the opportunity to cover the July 5-6 conference in Vienna.

A Reuters spokesperson stated that "we believe that transparency and a free press serve both readers, markets, and the public interest, and we object to this restriction on coverage," adding that "Reuters will continue to cover OPEC in an independent, impartial, and reliable way, in keeping with the Thomson Reuters Trust Principles."

A Bloomberg statement expressed concern that OPEC was excluding journalists, urging to allow them "for the sake of market transparency."

The same media outlets were denied admission to OPEC's Vienna headquarters on June 4 with no explanation for the three organizations' exclusion.

Other media outlets were formally invited to the event on Tuesday via email. Included are the Financial Times and trade publication Argus. S&P Global Commodity Insights, known as Platts, was additionally among the invitees.