U.S. President Barack Obama ordered new measures to boost the U.S. ability to stop mass atrocities such as genocide and bar perpetrators of war crimes from entering the United States.

The order sets up an Atrocity Prevention Board of government agencies to coordinate responses to such events within the administration.

Obama noted in a statement that 66 years after the Holocaust and 17 years after the genocide in Rwanda the United States still lacked a "comprehensive policy framework" for stopping large-scale atrocities.

Obama directed his administration to study a range of economic, diplomatic and other actions that can be taken in such cases.

The U.S. president cited the likelihood of the mass slaughter of civilians in Benghazi, Libya, in March when the United States joined NATO's military action. In recent weeks, he has been criticized for not doing more to stop Syria's killing of unarmed protesters which, while it falls short of genocide, has intensified in recent days.

Through a presidential proclamation, Obama also expanded the grounds for denying entry into the United States to include a larger number of human rights violators such as those who commit "war crimes and crimes against humanity", Reuters reported.

As a candidate for President, Obama repeatedly vowed to recognize the Armenian Genocide once in office, vowing "a principled commitment to commemorating and ending genocide." But since 2009, Obama has declined to use the word in the face of furious resistance from Turkey, a key NATO ally.