Hadi was his vice president, but has been supported by the international community and regional powers to transition Yemen to a more democratic rule. He faces the challenge of restructuring a security sector studded with Saleh loyalists and family members.
The transition also included holding a national dialogue conference for the country's divided political groups that include southern secessionists and northern rebels. Hadi also has to deal with one of the most active branches of al-Qaida in the world, which has destabilized the country's south.
The country's constitution and electoral system must also be reformed, and general elections were expected to be held by the end of the transition period in two years.
Hadi's term in office "ends with the election of a new president. It will not end in February 2014," Benomar said.
He added that the start of a national dialogue launched in March was delayed for technical reasons, but has since been obstructed by loyalists to Saleh, who for instance did not attended a meeting Monday in an effort to delay its convening.
"I say this is extortion and doesn't serve Yemen's higher interests," he said.
He also blamed Saleh and his supporters for derailing security sector reforms.
"Some new appointments in the military and security sectors announced by Hadi have been rejected by some political leaders. There was obstruction and rebellion. This didn't aid in a smooth transition for the political process," Benomar said.
Members of the national dialogue conference said Saleh himself has objected to an article in the dialogue that would ban former security officials from running for the office of president until 10 years have passed since they quit the military. The article would prevent Saleh's son, a prominent military leader, from running for office.
Benomar said the U.N. Security Council is closely following developments in Yemen, meeting every two months to review reports presented by him on the situation in the country. He said the council is supportive of Hadi, and is aware of political obstruction from his predecessor and his loyalists.
"The Council warns the obstructionists, and affirms that they will not be able to undermine the political process," Benomar said. "The Council is aware that there is systematic obstruction."
Also on Monday, Assistant to U.S. President for Homeland Security and Counterterrorism Lisa Monaco spoke with Hadi to "reaffirm the U.S. government's strong support for Yemen's political transition."
She commended him on the efforts to move forward with the national dialogue and reaffirmed Washington's commitment to implement its outcome, foster economic development, and combat the security threat from al-Qaida.