The United States plans to provide about $US100 million worth of new aid to the Syrian opposition.
A US official says that could mean an expansion of non-lethal military assistance for certain rebel groups to include body armour and night-vision goggles.
Secretary of State John Kerry is expected to announce the new aid package at an international conference on Syria in Turkey.
The new assistance will stop short of supplying weapons or other lethal equipment to rebels fighting to overthrow the Syrian President Bashar al-Assad, and it is also far less than some US politicians and Syrian opposition leaders are seeking.
