Forces from Gulf Arab countries will help with maintaining order in Bahrain and some forces have already arrived in the country, according to press reports.
"Forces from the Gulf Cooperation Council have arrived in Bahrain to maintain order and security," Nabeel al-Hamer, a former information minister and adviser to the royal court, said on his Twitter feed, quoted by Reuters.
Bell Pottinger, the official public relations firm for the Bahrain government, told CNBC it could neither confirm nor deny the reports.
The US embassy confirmed foreign military elements entering Bahrain along King Fahad Causeway, the Public Affairs Officer told CNBC.
It is not clear whether the possibility of a GCC force entering a sovereign member-state for policing purposes is technically legal according to the GCC charter, which stipulates that if a sovereign state is threatened, than member states can use force to deter that threat.
Clause two of the Charter’s Section on Military Cooperation in the GCC states that any danger threatening a GCC state is a threat to all of them.
The wording is such that it could potentially be seen to include a threat from within. But a non-Bahraini force policing the country could create even further sectarian tensions as one of the protestors' main grievances has been that a majority Shiite Bahraini population was subject to a police force full of non-Bahrainis.
Thousands of anti-government protestors pushed back Bahrain security forces Sunday after riot police used tear gas and shot rubber bullets at demonstrators in the country's financial district.
Police forces retreated later in the day, with protestors manning barricades along a section of Sheik Khalifa Highway that runs through the downtown area of Manama.