RNA - "The Department of Defense is working closely with the Department of State to ensure the security of our Embassy and personnel in Baghdad," Esper said in a statement on Tuesday.
"We are sending additional forces to support our personnel at the embassy,” he added.
"We have taken appropriate force protection actions to ensure the safety of American citizens, military personnel and diplomats in country, and to ensure our right of self-defense," Esper said.
"As in all countries, we rely on host nation forces to assist in the protection of our personnel in country, and we call on the Government of Iraq to fulfill its international responsibilities to do so," he continued.
The Pentagon chief gave no further details, but the deployment is reportedly likely to involve a small number of American marines.
On Monday, Iraqi Prime Minister Adel Abdul Mahdi condemned the "unacceptable vicious assault" by the US that killed more than two dozen Iraqis and injured scores more.
Thousands of angry protests managed to reach the US diplomatic mission which is located in Baghdad's heavily fortified Green Zone, chanting “Death to America” and burning US flags.
The protesters further held up signs calling for the US mission to be shut down and for the parliament to order US forces to leave Iraq.
“Parliament should oust US troops, or else we will,” one poster read.
Reuters cited two Iraqi Foreign Ministry sources as saying that the US ambassador and other staff were evacuated from the embassy out of security concerns as protests raged outside.
Only a few embassy protection staff were left behind, according to the news agency.
American forces deployed inside the compound have fired tear gas, flash bangs and stun grenades to disperse the crowd.
The protesters have breached the outer wall of the high-security compound. They have sprayed the words “Closed in the name of the people” on the gates of the American mission, throwing bricks and stones at the surveillance cameras around the building.
Reacting to the developments in Iraq, US President Donald Trump said in a tweet that Iran was to blame and would be held “fully responsible.”