A key Syrian opposition group on Sunday accused the Iraqi government of intervening in Syria and "attacking the Syrian people", a day after deadly border clashes between rebels and Iraqi forces.
"After the Iraqi government headed by (Prime Minister) Nuri al-Maliki gave political and intelligence support to the Syrian regime... the Baghdad regime has moved on to a new level of intervention in Syrian affairs," said the Syrian National Council.
It charged that Baghdad was "attacking the Syrian people, their basic rights and their territorial sovereignty."
An Iraqi official said on Sunday that an Iraqi soldier was killed and three people wounded, including a soldier, inside northern Iraq during a gunfight the day before between Iraqi forces and Syrian rebels at the Yaarubiyeh border crossing.
Four Syrian soldiers were also treated at an Iraqi hospital after the clash, the official added.
The SNC has called on the Arab League and the United Nations to condemn Baghdad for the attack "on Syrian sovereignty", saying the international community should "at the very least condemn this aggressive behaviour".
Baghdad has pointedly avoided calling for the departure of Syrian President Bashar al-Assad, who is locked in a bloody civil war with rebels opposed to his regime, and has instead urged an end to violence by all parties.
But US officials have repeatedly called on the Iraqi government to halt Iranian flights to Syria via Iraqi airspace, which they say are transporting weapons to Assad's forces.
As the violence has escalated in Syria, the country's crisis has spilled over into neighbouring countries Lebanon and Iraq.