The conflict, which has now killed more than 160,000 people, has paralyzed the UN Security Council, riven by sharp disagreements between Western nations and Damascus ally Russia.
"It is essential to stem the flow of arms pouring into the country," Ban said in a speech at the Asia Society in New York.
"It is irresponsible for foreign powers and groups to give continued military support to parties in Syria that are committing atrocities."
"I urge the Security Council to impose an arms embargo. If divisions in the Council continue to prevent such a step, I urge countries to do so individually," he added.
"Syria's neighbors should enforce a firm prohibition on the use of their land borders and airspace for arms flows and smuggling into Syria."
Iran and Russia are the main arms providers to the Syrian government, as Gulf states are to the opposition.
Asked for his reaction to Ban's call, Russian Ambassador Vitaly Churkin told reporters it was unrealistic and drew parallels with the uprising against Libyan leader Moamer Kadhafi.
"In Libya there was an arms embargo and weapons were flowing freely to various opposition groups and are still floating all over Africa," he said.
"We do not want to go in that direction."
Four Western resolutions on Syria have been vetoed by Russia, blocking efforts to enforce the delivery of aid and refer both sides to the International Criminal Court.
Ban spoke of his "anger and disappointment" at calculations that so little can be done to end the conflict, saying the world must not abandon Syrians and the region "to never-ending waves of cruelty."
International envoy Lakhdar Brahimi resigned at the end of May after two rounds of peace talks yielded no concrete results and Syrian President Bashar al-Assad was re-elected in June.
Ban said the election did "not meet even minimal standards for credible voting" and that he would soon name a new envoy, admitting however that he or she "will not be able to wave a magic wand."
Ban said those who oppose the International Criminal Court but who claim to support accountability must present "credible alternatives," adding perpetrators must be called to account.
China and Russia vetoed a Western resolution on May 22 that sought to refer both sides to the ICC for war crimes.
The UN chief said there could never be a permanent military victory to the war in Syria and promised that the United Nations would not abandon Syrians who desired peace.
- Sectarian warfare a 'disaster' -
Ban also demanded that the regional overflow and Al-Qaeda-linked extremist threat must be addressed, pointing to the flow of arms and fighters across the porous border into crisis-stricken Iraq.
He warned that military strikes against Iraq's jihadists could prove counterproductive without any movement toward inclusive government in the country of Sunni Arabs, Kurds and Shiites.
"It is imperative for the government and its backers to ensure that no reprisals are carried out against Sunni communities in revenge for the barbaric acts by ISIS," he said.
Ban said the group presented a threat to all communities in Iraq, urging all Iraqis to work together.
"Sectarian warfare is a disaster for all, it generates a vicious circle," he said.
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"It is essential to stem the flow of arms pouring into the country," Ban said in a speech at the Asia Society in New York.
"It is irresponsible for foreign powers and groups to give continued military support to parties in Syria that are committing atrocities."
"I urge the Security Council to impose an arms embargo. If divisions in the Council continue to prevent such a step, I urge countries to do so individually," he added.
"Syria's neighbors should enforce a firm prohibition on the use of their land borders and airspace for arms flows and smuggling into Syria."
Iran and Russia are the main arms providers to the Syrian government, as Gulf states are to the opposition.
Asked for his reaction to Ban's call, Russian Ambassador Vitaly Churkin told reporters it was unrealistic and drew parallels with the uprising against Libyan leader Moamer Kadhafi.
"In Libya there was an arms embargo and weapons were flowing freely to various opposition groups and are still floating all over Africa," he said.
"We do not want to go in that direction."
Four Western resolutions on Syria have been vetoed by Russia, blocking efforts to enforce the delivery of aid and refer both sides to the International Criminal Court.
Ban spoke of his "anger and disappointment" at calculations that so little can be done to end the conflict, saying the world must not abandon Syrians and the region "to never-ending waves of cruelty."
International envoy Lakhdar Brahimi resigned at the end of May after two rounds of peace talks yielded no concrete results and Syrian President Bashar al-Assad was re-elected in June.
Ban said the election did "not meet even minimal standards for credible voting" and that he would soon name a new envoy, admitting however that he or she "will not be able to wave a magic wand."
Ban said those who oppose the International Criminal Court but who claim to support accountability must present "credible alternatives," adding perpetrators must be called to account.
China and Russia vetoed a Western resolution on May 22 that sought to refer both sides to the ICC for war crimes.
The UN chief said there could never be a permanent military victory to the war in Syria and promised that the United Nations would not abandon Syrians who desired peace.
- Sectarian warfare a 'disaster' -
Ban also demanded that the regional overflow and Al-Qaeda-linked extremist threat must be addressed, pointing to the flow of arms and fighters across the porous border into crisis-stricken Iraq.
He warned that military strikes against Iraq's jihadists could prove counterproductive without any movement toward inclusive government in the country of Sunni Arabs, Kurds and Shiites.
"It is imperative for the government and its backers to ensure that no reprisals are carried out against Sunni communities in revenge for the barbaric acts by ISIS," he said.
Ban said the group presented a threat to all communities in Iraq, urging all Iraqis to work together.
"Sectarian warfare is a disaster for all, it generates a vicious circle," he said.
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