Bahrain’s opposition said it considered any foreign military intervention to be an “overt occupation”.

It called for an emergency meeting of the UN Security Council, and appealed for the international community to act to ensure the “protection of the people of Bahrain from the danger of foreign military intervention.”

The Saudi intervention comes two days after Robert Gates, the US Defence Secretary, visited Manama and held talks with the king in which he said he urged them to undertake rapid and significant reform.