Foreign ministers of the Friends of Syria group meeting in Qatar have agreed to provide urgent support to rebels fighting President Bashar al-Assad.
Qatar's Prime Minister Sheikh Hamad bin Jassim bin Jaber al-Thani said providing arms may be the only means of achieving peace.
He said moral support for the rebels was not sufficient and a balance must be achieved on the ground so the regime can accept negotiations.
Ministers from Britain, Egypt, France, Germany, Italy, Jordan, Qatar, Saudi Arabia, Turkey, the United Arab Emirates and the United States attended the talks.
The group's joint statement said the members had agreed to "provide urgently all necessary materiel and equipment to the opposition on the ground, each country in its own way in order to enable them to counter brutal attacks by the regime and its allies".
Support would be channelled through the Western-backed rebel military command but the statement did detail what would be provided, the BBC reports.
The group also called on the immediate withdrawal of Lebanese Hezbollah and Iranian fighters from Syria.
The meeting in Qatar's capital, Doha, comes a week after the US announced it would provide Syrian rebels with direct military aid.
US Secretary of State John Kerry said he decision to provide military support to the rebels was "not to seek a military solution" but to give the rebels more power in negotiating an end to the conflict.
Mr Kerry said the group was still pushing for a peace conference in Geneva between the two opposing sides in Syria.
More than 90,000 people have died in more than two years of conflict. The Syrian government says it is fighting foreign-backed terrorists.
