UN chief Ban Ki-moon appealed for global efforts to end calamity in Syria at the general debate of the 67th session of the United Nations General Assembly while the West and Arab countries voiced loud support for Syrian rebels.

UN Secretary-General Ban Ki-moon addresses the 67th session of the UN General Assembly's annual general debate at the UN headquarters in New York, the United States, Sept. 25, 2012. [Xinhua]

Addressing the general debate opened Tuesday, Ban called for efforts to end the violence and flows of arms to both sides in the Syrian crisis and launch a Syrian-led transition in the Middle East country at an early date.

"The situation in Syria grows worse by the day," he said. "The crisis is no longer limited to Syria; it is a regional calamity with global ramifications."

Ban called the crisis "a serious and growing threat to international peace and security which requires Security Council action," saying the international community "should not look the other way as violence spirals out of control."

"It is the duty of our generation to put an end to impunity for international crimes, in Syria and elsewhere," said Ban.

Without mentioning U.S. support for the Syrian opposition, U.S. President Barack Obama said his country stands for a Syria that "is united and inclusive, where children don't need to fear their own government, and all Syrians have a say in how they are governed, Sunnis and Alawites, Kurds and Christians."

"That is the outcome that we will work for -- with sanctions and consequences for those who persecute, and assistance and support for those who work for this common good," Obama said.

However, a senior official of the U.S. State Department said Tuesday that the United States would give more aid to Syrian rebels this week to help them "protect themselves and defend themselves."

The remarks were made after the UN-Arab League Joint Special Representative for Syria Lakhdar Brahimi met with U.S. Secretary of State Hillary Clinton who will host talks of the "Friends of Syria" group on Friday.

The United States is also providing some 25 million dollars in non-lethal aid to Syrian rebels to fund things such as communication equipment.

Also addressing the general debate on Tuesday, French President Francois Hollande urged the United Nations to support Syrians' requests and protect rebel-controlled area which he called "liberated zones," saying France would recognize a government formed by Syrian opposition.

Hollande also warned that if the Syrian government used chemical weapons, the international community would take actions.

Dutch Foreign Minister Uri Rosenthal said in a meeting with Ban Ki-moon that the UN should act more severely against the Syrian government.

Last week, Rosenthal advocated making sanctions against the Syrian government more efficient and called for more sanctions such as blocking access to technologies required to censor websites or track people online.

Qatari Emir Sheikh Hamad bin Khalifa Al-Thani called for Arab intervention and a non-fly zone in Syria at the general debate on Tuesday, saying the UN Security Council failed to stop the civil war in Syria.

Qatar, Saudi Arabia and Turkey strongly support the mainly Sunni Muslim Syrian rebels while the Syrian government is controlled by Alawite minority, an offshoot of Shiite Islam.

On Tuesday in Syria, two explosive devices planted by "terrorists" went off inside a school in the country's capital Damascus, injuring seven people.

Activists said the blasts were caused by seven explosive charges that targeted the school "which has been used by pro-government militias and security officers as a command center."