Foreign Secretary William Hague and his Friends of Syria counterparts have agreed to "provide urgently all the necessary material and equipment" to Syrian rebels opposed to President Bashar al-Assad.
The UK has not committed to supply arms to the Syrian rebels, but each of the group's 11 members will "act in its own way" to support them.
In a communique issued after talks in Qatar, the ministers demanded the withdrawal of Hezbollah militias and fighters from Iran and Iraq who had sided with Assad's regime.
ITV News reporter Martha Fairlie reports:
All military support will be channeled through the Syrian Supreme Military Council, the Friends of Syria said.
The communique also called for fighters supporting Assad to be prevented from crossing into Syria from neighbouring counties.
The foreign ministers also pledged to pursue "all appropriate avenues" at the United Nations to "support and protect the Syrian people".
– Foreign Secretary William Hague
There's been a very strong common sense of purpose among the eleven countries gathered here today, all desperately concerned about foreign intervention in Syria by Iran and by Hezbollah and by the seriousness of the humanitarian situation.
I think the main things in common and agreed are that we're all concerned about that humanitarian situation.
The United Kingdom ... is helping to lead the way with another £175 million contribution to the humanitarian situation.
US Secretary of State John Kerry called for an urgent political resolution to the crisis, saying that unless the bloodshed stops, the region could descend into a chaotic sectarian conflict.
Mr Kerry said, "We're all aiming to achieve a political solution, a political settlement, in Syria but that political settlement will not come about if the opposition can be destroyed by force".
While he offered no specifics, Kerry said the assistance would help change the balance on the battlefield, where regime forces have scored recent victories.
Ministers from Qatar, Saudi Arabia, the United Arab Emirates, Jordan, Egypt, Turkey, Germany, France, and Italy also attended the summit.