Secretary of State John Kerry said the US will channel $60 million in aid to Syrian groups the US chooses, which is a clear message that jihadi groups must be excluded from the aid.
Although the US aid is "non lethal", this is the biggest package and strongest back-up yet given so far by the US to Syrian rebels.
Mr Kerry said "no people should live in fear of their so called leaders" and "we must meet the moment."
US backing of the Syria rebels today is at its most public, financial, open and morally clear.
More top news
A summary of the day's election campaign stories in under one minute.
A Twitter argument has erupted between One Direction's Louis Tomlinson, his former bandmate Zayn Malik and music producer Naughty Boy.
Labour supporters have rallied around Ed Miliband by recreating his now-infamous bacon sandwich picture, posted under the hashtag #JeSuisEd.