London/Manama, Asharq Al-Awsat- Gulf Cooperation Council (GCC) security forces entered Bahrain yesterday at the request of Manama to help protect government facilities from the threat of unrest, after weeks of protests in the Gulf kingdom.

The Saudi government said it had responded to a call for help from its neighbor as Saudi-led forces from the Gulf countries’ joint Peninsula Shield Force crossed the causeway into Bahrain.

“The council of ministers has confirmed that it has answered a request by Bahrain for support,” the Saudi government said in a statement carried by the SPA state news agency.

Under an agreement of the six-country Gulf Cooperation Council (GCC), “any harm done to the security of a member state is considered a harm done to the security of all members,” it said.

The United Arab Emirates also said it had sent some 500 police to help “defuse tension,” according to Foreign Minister Sheikh Abdullah bin Zayed al-Nahayan.

A statement on the state-run Bahrain News Agency said troops from the GCC’s Peninsula Shield Force have been deployed “in line with the principle of common destiny bonding.” The bloc is made up of Saudi Arabia, Oman, Kuwait, Bahrain, Qatar and the United Arab Emirates.

The reason for the mission was “the common responsibility of the GCC countries in maintaining security and stability,” the statement said.

The Peninsula Shield Force was created in the 1980s. Military units under a GCC command have been sent to Kuwait, including during the 1991 U.S.-led campaign to oust Saddam Hussein’s force and in 2003 before the invasion of Iraq.

The Shiite-led opposition alliance said any foreign force would be treated as an invading army.

“We consider the arrival of any soldier, or military vehicle, into Bahraini territory… an overt occupation of the kingdom of Bahrain and a conspiracy against the unarmed people of Bahrain,” said an opposition statement.

Bahrain has been gripped by its worst unrest since the 1990s after protesters took to the streets last month, inspired by uprisings that toppled the leaders of Egypt and Tunisia.

Thousands are still camped out at the Pearl roundabout, having returned since the army cleared out the area last month.

Washington has urged Bahrain to use restraint and repeated the call to other Gulf nations on Monday.

“We urge our GCC partners to show restraint and respect the rights of the people of Bahrain, and to act in a way that supports dialogue,” White House spokesman Tommy Vietor said.

Iran’s foreign ministry spokesman Ramin Mehmanparast said on Tuesday military intervention in Bahrain by Gulf States is “unacceptable” and it will complicate the already volatile situation there.

White House spokesman Jay Carney called on the Gulf forces to respect the rights of the people of Bahrain.

“We urge the government of Bahrain… as well as other GCC countries, to exercise restraint and not to meet the non-violent protests of people legitimately expressing their concerns… with any kind of physical violence.”

But Carney declined to call for the forces to be pulled out, saying: “This is not an invasion of a country.”