Yemen's President Abdrabuh Mansur Hadi backed by his US counterpart Barack Obama vowed to fight "terrorism" after a suicide bomber killed 96 soldiers in relatiation for an army offensive against Al-Qaeda.
Monday's attack in the heart of the capital Sanaa, in which about 300 soldiers were injured, came as soldiers were rehearsing for a parade to mark the reunification of Yemen.
An official said the parade, which had been scheduled to take place Tuesday at Sabeen Square -- scene of the suicide blast -- had been replaced with a "symbolic" ceremony held at the Defence and Aviation college in Sanaa.
The ceremony was attended by Hadi, who made no speech and left soon after the event ended.
Army chief of staff Ali al-Ashwal vowed the military would not be deterred from its offensive against the jihadists.
"The barbaric attack on Sabeen Square will not scare us and will not prevent us from going ahead with out war on these evil elements," he told the ceremony.
"Our war on them will not stop until we free our land," said Ashwal, who was among the officials, including defence minister Mohammed Nasser Ahmed, apparently targeted in the attack.
Al-Qaeda in the Arabian Peninsula (AQAP), the name given to the group's Yemen branch, claimed responsibility for the attack which it said targeted "the defence minister and other leaders of the US war on our people in Abyan" province in the south.
"Even if the defence minister and his aides escaped this operation, we will not tire ... we are in a war to defend our blood which is violated in Abyan, and war only breeds war," it said in a statement posted on jihadist Internet forums.
Police Colonel Abdul Hamid Bajjash, the officer in charge of security at the blast site, said Yemen's defence minister was present at the time of the explosion but escaped unharmed.
He said the bomber detonated his explosives as soldiers from the government's central security forces, commanded by a nephew of former president Ali Abdullah Saleh, rehearsed for Tuesday scheduled army parade to mark the 22nd anniversary of the unification of north and south Yemen.
Yemen's military launched a major offensive in Abyan on May 12 in a bid to drive Al-Qaeda linked jihadists out of towns and cities in the restive province where they have held sway since May last year.
Since the offensive began, 234 people have been killed, according to a tally compiled by AFP, including 158 Al-Qaeda fighters, 41 military personnel, 18 local militiamen and 17 civilians.
"The war on terror will continue until it is completely destroyed regardless of the sacrifices," Yemen's president, Abdrabuh Mansur Hadi, said in a statement carried by state news agency Saba after Monday's massive attack, the deadliest since he took power in February.
US President Barack Obama on Monday said the United States was very worried about the threat posed by AQAP and pledged to work with the Yemeni government to crack down the group, blamed for several Yemeni-based attempts to blow up US airliners and cargo planes.
"We are very concerned about Al-Qaeda and extremist activity in Yemen," Obama told reporters at a NATO summit in Chicago devoted to ensuring that Al-Qaeda is not allowed to regroup in another one-time terror haven, Afghanistan.
The United States has carried out regular drone strikes against AQAP suspects in Yemen.
In May, several US drone strikes killed a number of Al-Qaeda militants including a top Al-Qaeda leader wanted following the disruption of a plot for a suicide bomber to wear a device sewn into custom fit underwear designed to bring down a passenger jet.
The plot mirrored another Yemen-based plot, on Christmas Day 2009, when a suicide bomber tried to bring down a US airliner over Detroit, but the device failed to properly explode.
UN Secretary General Ban Ki-moon said those behind the attack must be brought to justice.
The European Union also condemned a "brutal and terrible" bombing, while Britain slammed the "cowardly" suicide bombing.