More than 100 countries on Wednesday recognized a new Syrian opposition coalition, further isolating the regime and opening the way for greater humanitarian assistance to the forces battling Bashar Assad.

The opposition has been under intense international pressure to create a more organized and representative body to receive foreign aid, so it formed the Syrian National Coalition in Doha, Qatar, in November, and it was widely applauded at the conference in Morocco.

"With every day that passes, the regime's hold on power weakens. Territory slips from its grasp. The opposition becomes more unified and organized," said U.S. Deputy Secretary of State for the Middle East William Burns. His boss, U.S. Secretary of State Hillary Rodham Clinton, was expected to attend the conference but canceled following an illness.

"We look to the coalition to continue creating more formal structures within the opposition and to accelerate planning for a democratic political transition that protects the rights, the dignity and the aspirations of all Syrians and all communities," Burns said. He also announced that the leadership of the new coalition has been invited to Washington.

As the conference was taking place, an explosion occurred near the Syrian Interior Ministry in Damascus, according to state TV, possibly another audacious rebel attack at the center of the regime's power. Fighting has intensified in the southern districts of the Syrian capital and its suburbs.

The world's recognition of the Libyan opposition gave it a huge boost in the battle against Moammar Gadhafi last year and paved the way for Western airstrikes. Military intervention does not appear to be in the cards for Syria, however, where the government has the powerful backing of Russia, China and Iran.

French Foreign Minister Laurent Fabius called the "Friends of the Syrian People" conference meeting in Marrakech, Morocco, "extraordinary progress." He noted that the European Union is now renewing its weapons embargo on Syria every three months, rather than annually, to be more flexible as the situation on the ground changes.

"We want to have the ability to continue or to change our attitude on this point. The fact that the coalition, which is asking for the right to defend itself, is now being recognized by a hundred countries _ yesterday the U.S. and first France _ I think this is a very important point."

The conference's final statement said Assad, Syria's president, has lost all legitimacy but stopped short of calling for him to step down, something attending ministers did say individually. The statement also warned that any use of chemical weapons "would draw a serious response" from the international community.

"I believe that of all the meetings we have had so far for the friends of Syria, this will turn out to be the most significant," British Foreign Secretary William Hague said at the final news conference.

The Syrian military's recent movement of chemical weapons prompted the United States to warn Assad that he would be "held accountable" if his forces used them against the rebels.

In Marrakech, conference members announced new humanitarian assistance for Syrians, including $100 million from Saudi Arabia and a fund to be managed by Germany and the United Arab Emirates for the reconstruction of the country after Assad falls. The U.S. announced $14 million in humanitarian aid as well.

Participants expressed worry over the 2 million displaced people in the country as well as the estimated 40,000 dead in 21 months of fighting.

Western countries have been reluctant to send arms to Syria, however. That's not the least because of their experience in Libya, where the West actively backed one side in a civil war in a country that later became awash in militant groups.

Syrian opposition members have repeatedly asked for increased military assistance.

"We need not only bread to help our people," opposition member Saleem Abdul Aziz al Meslet told The Associated Press. "We need support for our Syrian army. We need to speed up things and get rid of this regime."

Part of the problem, however, is that the many of the recent battlefield successes by the rebels appear to be by groups with jihadi tendencies, like Jabhat al-Nusra, which the U.S. declared had ties to al-Qaida and put on the terrorism watch list.

The move caused a stir among the Syrian opposition.

In his speech at the conference, the newly selected president of the Syrian National Coalition, Mouaz al-Khatib, urged the U.S. to "reconsider" the designation since the Jabhat al-Nusra group was performing a valuable service in the battle against the regime.

The West fears that Islamist fighters will come to dominate the revolt. They have been at the vanguard of the conflict, in part because of their greater fighting experience. They also have claimed responsibility for a string of bomb attacks striking at the very heart of the regime, such as Wednesday's explosion in Damascus.

"The step that we took with regard to the designation of the al-Nusra Front raises an alarm about a very different kind of future for Syria, about the direction that a group like al-Nusra will try to take Syria to impose its will and threaten the socials fabric of Syria," Burns told journalists.

In his speech at the conference, al-Khatib did condemn "all forms of extremism" _ a veiled reference to the jihadi groups operating in the country. He specifically called for reconciliation with the country's Alawite minority, from which Assad comes, and urged Alawites to launch a campaign of civil disobedience against the regime.

"We call on them to accept the extended hand and work together against the violence of the regime," he said.