NEW : White House counterterrorism adviser John Brennan urges unity and peace . The U.S. government has been under pressure to explain the killing of a top al Qaeda operative in Yemen last month after he was identified as Anwar al-Awlaki, an American-born cleric who had joined Al Qa@@ President Saleh agreed on Wednesday to step down from power . The decree stipulates that the vote be monitored by an election committee .
NEW : White House counterterrorism adviser John Brennan urges unity and peace . Yemen 's vice president issues a decree calling for a vote to be held February 21 . President Saleh agreed on Wednesday to step down from power . The decree stipulates that the vote be monitored by an election committee .