A car bomb explosion killed at least 26 elite Republican Guards outside the presidential palace of Yemen in Mukallah on Saturday, it has been reported.

"The bodies of 26 soldiers were taken to the mortuary and there are many others wounded," Al Arabiya News quoted a medic at the Ibn Sina hospital in Mukallah as saying.

The attack, apparently by a suicide bomber, took place a few hours after Abdrabbuh Mansour Hadi took the oath of office as the new president of Yemen, according to an AFP report.

"A pick-up truck driven by a suicide bomber exploded at the entrance of the presidential palace in Mukalla, capital of Hadramawt province," the AFP has quoted a security official as saying.

Hadi has taken over as the president of Yemen at the end of months of protest against Ali Abdullah Saleh, who had ruled the country for 33 years.

In a televised address to the nation after becoming the president, Hadi vowed to take strict action against al-Qaeda and reinstate peace and security in the nation.

"It is a patriotic and religious duty to continue the battle against al-Qaida. If we don't restore security, the only outcome will be chaos," Hadi said during the address to the nation.