Iranian lawmaker Mostafa Kavakebian announced May 6 that the Iranian Parliament was conducting a review of the "massacre of Bahraini people by al-Saud and al-Khalifa (regimes)."
Tehran is upset with a decision by Saudi Arabia to send forces to Bahrain under the auspices of the Gulf Cooperation Council.
The minority Sunni leadership in Bahrain is struggling to control mounting frustration from the country's Shiite majority.
Ali Larijani, the speaker of the Iranian Parliament, in a letter to the Inter-Parliamentary Union that Bahrain's reaction to the unrest was out of step with human rights norms.
"Parliaments, as representatives of the people, are expected to act upon their human duty and react to the massive violation of human rights and the critical situation in Bahrain ... and to help prevent further continuation of the current situation," he was quoted by the semi-official Fars News Agency as saying.
The IPU describes itself as the "focal point for world-wide parliamentary dialogue and works for peace and co-operation among peoples and for the firm establishment of representative democracy."
Iran faced its own human rights backlash for its response to the unrest that greeted the contested 2009 re-election of Iranian President Mahmoud Ahmadinejad.