Washington (CNN) -- As military forces from the Gulf Cooperation Council arrived in Bahrain to help the kingdom control a wave of anti-government protests, the Obama administration and U.N. Secretary-General Ban Ki-moon urged GCC members -- including Saudi Arabia -- to act with restraint and to allow the citizens of Bahrain to demonstrate peacefully.

The influx of foreign security forces to control a domestic uprising sparked questions at the White House press briefing on Monday. Spokesman Jay Carney told reporters the United States is urging "all of our GCC partners to show restraint and to respect the rights of the people of Bahrain and to act in a way that supports dialogue instead of undermining it."

"We urge restraint, we urge non-violence in response to non-violent protesters, the respect for the universal rights of people in the region to gather peacefully, to voice their opinions, to have their grievances heard by their governments, and to have greater participation in the political process," Carney said.

A spokesperson for Ban Ki-moon, echoed that sentiment.

"The Secretary-General is troubled by the growing violence in the Kingdom of Bahrain that has left many people injured over the past few days," said spokesperson Anne Siddall in a prepared statement. "He notes with concern that troops from the Kingdom of Saudi Arabia and the United Arab Emirates under the auspices of the Gulf Cooperation Council have reportedly entered the territory of Bahrain today."

"The Secretary-General strongly believes that peaceful means should be adopted to ensure national unity and stability. He appeals to all concerned to exercise maximum restraint and to do everything possible to prevent the use of force and further violence," Siddall's statement read.

The GCC action caught Secretary of Defense Robert Gates and Joint Chiefs of Staff Chairman Adm. Mike Mullen by surprise, a Pentagon spokesman said Monday

"Secretary Gates nor Adm. Mullen were given any indication that Saudi or other GCC forces would deploy to Bahrain," said Col. David Lapan. "We have communicated to all parties our concerns regarding actions that could be provocative or inflame sectarian tensions."

In Paris, after a meeting with U.S. Secretary of State Hillary Clinton, the foreign minister of the United Arab Emirates, Abdullah bin Zayed al Nahyan, told reporters that the Bahrain government asked the council to "look at ways to help them to defuse the tension in Bahrain." The U.A.E. is a member of the Gulf Coalition Council and the minister said his country had sent approximately 500 police officers to Bahrain to assist.

The GCC, in a statement, said it was acting in unity with other members to carry out its responsibility for "maintaining security and stability."

Although Bahrain's protesters are making primarily economic and political demands, there is a sectarian dimension: Bahrain's population is 70% Shiite; the royal family is Sunni, as is the royal family of Saudi Arabia. Saudi Arabia recently has seen small demonstrations among its minority Shiites.

The United States has been watching the growing demonstrations in Bahrain, led more and more by hardliners, with concern, fearing that Iran, a Shiite-ruled nation, could exploit the instability. The protesters have denied they are being influenced by Iran.

Last month, President Barack Obama welcomed plans by Bahrain's King Hamad bin Isa al-Khalifa to make changes to his cabinet and proceed with reforms. But a few days ago Defense Secretary Robert Gates cautioned that "baby steps" would not be sufficient to meet protesters' demands.

Bahrain is the key banking and financial center in the Gulf. It also plays a crucial role in U.S. defense interests in the region. The U.S. Fifth Fleet is headquartered in Bahrain, and Bahrain is the only Arab state to have led one of the coalition task forces that patrol the Persian Gulf. U.S. military access to Bahrain also supports operations in Iraq.

CNN's Tim Lister contributed to this story.